9. A content item retrieval system comprising: a base location extractor module configured to determine multiple base locations, based on GPS information or user entry, each base location being a location from which to apply a corresponding criterion distance-determined granularity thresholding for setting a threshold for location similarity in selecting or rejecting target items for content item retrieval, wherein criterion distance-determined granularity thresholding is applied for each base location of the multiple base locations separately based on differences in distance between farther locations being less important than between equally distant closer locations, further wherein the farther in distance moved from a corresponding base location of the multiple base locations, the less important, in terms of determining similarity, are differences in distance between locations of different content items at the corresponding further distances from the corresponding base location; a location data extractor module configured to extract, as a first anchor item location, location data for a first identified anchor content item and to determine, as a criterion distance, a distance determined between a corresponding base location and the first anchor item location, the first identified content item for designating which candidate content items for which a content type is not known or specified by a user are to be retrieved; a threshold setter module configured to set a first threshold based on the criterion distance that the candidate content items must meet to be selected, wherein the first threshold comprises an assigned value on a scale of 1 to 10, where a value of 1 indicates a very small distance between a corresponding base location and candidate content item and a value of 10 indicates a great distance between the corresponding base location and candidate content item, and wherein the criterion distance is determined, using criterion distance-determined granularity thresholding, as a distance between the corresponding base location of the multiple base locations and the first anchor item location, further wherein the distance from the corresponding base location is ranked on the scale and as the distance from the corresponding base location increases, then longer distances are encompassed by fewer gradations of the scale, such that distance granularity on the scale is higher for locations geographically closer to the corresponding base location than for locations further away from the corresponding base location; said location data extractor module further being configured to extract, as a first candidate location, the location data for a first candidate content item, and to determine, as a first candidate distance, the distance between the corresponding base location of the multiple base locations and the first candidate location; a selector module configured to select the first candidate content item as similar for content item retrieval based on (i) the first candidate distance that corresponds to the distance between the corresponding base location of the multiple base locations and the first candidate location and (ii) the first threshold that is based upon the criterion distance, wherein the first candidate content item is selected as being similar to the first identified content item in response to the determined first candidate distance, when compared to the first threshold, being within or with the first threshold; a result output module configured to output a selection signal for indicating retrieval of the first candidate content item when the first candidate location of the candidate content item is selected as being similar to the first identified content item for content item retrieval; a controller configured to coordinate an overall functioning of respective modules; a user interface; and a storage device, wherein said controller is further configured to interact with the user interface and the storage device, the storage device for storage of content items subject to being retrieved, wherein the controller, the base location extractor, the location extractor, the threshold setter, the selector, and the result output modules, portions thereof, and the retrieval system as a whole, comprise a combination of hardware, software, and firmware configured to perform the corresponding functions of the respective controller and modules.
9. A content item retrieval system comprising: a base location extractor module configured to determine multiple base locations, based on GPS information or user entry, each base location being a location from which to apply a corresponding criterion distance-determined granularity thresholding for setting a threshold for location similarity in selecting or rejecting target items for content item retrieval, wherein criterion distance-determined granularity thresholding is applied for each base location of the multiple base locations separately based on differences in distance between farther locations being less important than between equally distant closer locations, further wherein the farther in distance moved from a corresponding base location of the multiple base locations, the less important, in terms of determining similarity, are differences in distance between locations of different content items at the corresponding further distances from the corresponding base location; a location data extractor module configured to extract, as a first anchor item location, location data for a first identified anchor content item and to determine, as a criterion distance, a distance determined between a corresponding base location and the first anchor item location, the first identified content item for designating which candidate content items for which a content type is not known or specified by a user are to be retrieved; a threshold setter module configured to set a first threshold based on the criterion distance that the candidate content items must meet to be selected, wherein the first threshold comprises an assigned value on a scale of 1 to 10, where a value of 1 indicates a very small distance between a corresponding base location and candidate content item and a value of 10 indicates a great distance between the corresponding base location and candidate content item, and wherein the criterion distance is determined, using criterion distance-determined granularity thresholding, as a distance between the corresponding base location of the multiple base locations and the first anchor item location, further wherein the distance from the corresponding base location is ranked on the scale and as the distance from the corresponding base location increases, then longer distances are encompassed by fewer gradations of the scale, such that distance granularity on the scale is higher for locations geographically closer to the corresponding base location than for locations further away from the corresponding base location; said location data extractor module further being configured to extract, as a first candidate location, the location data for a first candidate content item, and to determine, as a first candidate distance, the distance between the corresponding base location of the multiple base locations and the first candidate location; a selector module configured to select the first candidate content item as similar for content item retrieval based on (i) the first candidate distance that corresponds to the distance between the corresponding base location of the multiple base locations and the first candidate location and (ii) the first threshold that is based upon the criterion distance, wherein the first candidate content item is selected as being similar to the first identified content item in response to the determined first candidate distance, when compared to the first threshold, being within or with the first threshold; a result output module configured to output a selection signal for indicating retrieval of the first candidate content item when the first candidate location of the candidate content item is selected as being similar to the first identified content item for content item retrieval; a controller configured to coordinate an overall functioning of respective modules; a user interface; and a storage device, wherein said controller is further configured to interact with the user interface and the storage device, the storage device for storage of content items subject to being retrieved, wherein the controller, the base location extractor, the location extractor, the threshold setter, the selector, and the result output modules, portions thereof, and the retrieval system as a whole, comprise a combination of hardware, software, and firmware configured to perform the corresponding functions of the respective controller and modules. 16. The system of claim 9 , further comprising: said location data extractor module being further configured to extract, as a second location, location data for a second identified content item, the second identified content item for designating which additional candidate content items are to be retrieved; and said threshold setter module being further configured to set the first threshold based on the first criterion distance and also on a second criterion distance, wherein the second criterion distance is determined as a distance between the base location and the second location.