14. A non-transitory computer-readable medium having stored contents that configure a computing system to perform a method, the method comprising: analyzing, by the configured computing system, a plurality of textual comments being supplied by human users during a prior time period and being related to a plurality of topics that are each mentioned in contents of one or more of the plurality of textual comments and that are identified from the analyzing; generating, by the configured computing system, a plurality of comment groups based on the identified topics, each of the generated comment groups being associated with one of the identified topics and including one or more of the plurality of textual comments that have contents mentioning the associated identified topic; determining, by the configured computing system, multiple terms of interest that are distinct from the plurality of topics, and assigning each of the multiple terms to one of multiple graph axes; determining, by the configured computing system, and for each of at least some of the plurality of topics, a relevance of one of the generated comment groups associated with the topic to the multiple terms based at least in part on the textual comments included in the one generated comment group; providing, by the configured computing system, information to initiate display of a multi-dimensional graph that includes the multiple graph axes and that includes visual indicators for multiple of the at least some topics on the multi-dimensional graph, wherein a position of each of the multiple topics on the displayed multi-dimensional graph is based on the determined relevance of the one generated comment group associated with the topic to the multiple terms and is based on the assignment of the multiple terms to the multiple graph axes, to enable a visual determination from the displayed multi-dimensional graph of relative relevance of the multiple topics to the multiple terms; identifying, by the configured computing system, a subset of the plurality of textual comments that are associated with a specified content category based on contents of the textual comments of the identified subset, the textual comments of the identified subset being included in multiple of the generated comment groups; determining, by the configured computing system, a subset of the multiple generated comment groups that correspond to the specified content category for the prior time period; discovering, by the configured computing system, additional content categories that are related to the specified content category, wherein each of the additional content categories corresponds to the topic of at least one of the determined subset of comment groups; and providing, by the configured computing system, indications of the determined additional content categories that are related to the specified content category.
14. A non-transitory computer-readable medium having stored contents that configure a computing system to perform a method, the method comprising: analyzing, by the configured computing system, a plurality of textual comments being supplied by human users during a prior time period and being related to a plurality of topics that are each mentioned in contents of one or more of the plurality of textual comments and that are identified from the analyzing; generating, by the configured computing system, a plurality of comment groups based on the identified topics, each of the generated comment groups being associated with one of the identified topics and including one or more of the plurality of textual comments that have contents mentioning the associated identified topic; determining, by the configured computing system, multiple terms of interest that are distinct from the plurality of topics, and assigning each of the multiple terms to one of multiple graph axes; determining, by the configured computing system, and for each of at least some of the plurality of topics, a relevance of one of the generated comment groups associated with the topic to the multiple terms based at least in part on the textual comments included in the one generated comment group; providing, by the configured computing system, information to initiate display of a multi-dimensional graph that includes the multiple graph axes and that includes visual indicators for multiple of the at least some topics on the multi-dimensional graph, wherein a position of each of the multiple topics on the displayed multi-dimensional graph is based on the determined relevance of the one generated comment group associated with the topic to the multiple terms and is based on the assignment of the multiple terms to the multiple graph axes, to enable a visual determination from the displayed multi-dimensional graph of relative relevance of the multiple topics to the multiple terms; identifying, by the configured computing system, a subset of the plurality of textual comments that are associated with a specified content category based on contents of the textual comments of the identified subset, the textual comments of the identified subset being included in multiple of the generated comment groups; determining, by the configured computing system, a subset of the multiple generated comment groups that correspond to the specified content category for the prior time period; discovering, by the configured computing system, additional content categories that are related to the specified content category, wherein each of the additional content categories corresponds to the topic of at least one of the determined subset of comment groups; and providing, by the configured computing system, indications of the determined additional content categories that are related to the specified content category. 27. The non-transitory computer-readable medium of claim 14 wherein the method further comprises: receiving, by the configured computing system, information about a succession of multiple comment groups that one or more users select; and providing, by the configured computing system, information to initiate display of information to at least one user about the succession of the multiple comment groups.