12. A computer system for filtering outbound content via inference detection, the computer system comprising: a processor; a memory coupled to the processor; a receiving mechanism configured to receive a first piece of outbound content associated with a destination identifier; a first keyword-extraction mechanism configured to extract keywords from the first piece of outbound content; a query formulation mechanism configured to issue a set of web queries that each includes one or more of the extracted keywords to obtain a set of search results; a second keyword-extraction mechanism configured to extract a set of candidate keywords from the search results returned by a search engine in response to the queries; an inference detection mechanism configured to perform inference detection using the set of search results for the extracted keywords; an expected-content mechanism configured to determine, from the set of candidate keywords, a set of expected-content keywords which are determined to be representative of the previously sent content based on the inference detection; a ranking mechanism configured to rank the set of candidate keywords extracted from the search results based on a confidence value generated using web-based inference detection, wherein the confidence value evaluates the candidate keyword's sensitivity to expected content; a selection mechanism configured to select one or more top ranked keywords to represent the first piece of outbound content; an inspection mechanism configured to determine whether outbound content is proper in response to receiving a second piece of outbound content, which involves performing one of: determining that the second piece of outbound content is associated with the first destination identifier, and the number of expected-content keywords present in the second piece of outbound content is below a first predetermined threshold; and determining that the second piece of outbound content is not associated with the first destination identifier, and the number of expected-content keywords present in the second piece of outbound content is above a second predetermined threshold; and a display mechanism configured to display the destination identifier for the second piece of outbound content, the selected one or more top ranked keywords to represent the first piece of outbound content, and at least one expected-content keyword selected to represent the second piece of outbound content in response to the second piece of outbound content being improper, thereby allowing a user to determine whether the second piece of outbound content has the proper content and destination identifier.
12. A computer system for filtering outbound content via inference detection, the computer system comprising: a processor; a memory coupled to the processor; a receiving mechanism configured to receive a first piece of outbound content associated with a destination identifier; a first keyword-extraction mechanism configured to extract keywords from the first piece of outbound content; a query formulation mechanism configured to issue a set of web queries that each includes one or more of the extracted keywords to obtain a set of search results; a second keyword-extraction mechanism configured to extract a set of candidate keywords from the search results returned by a search engine in response to the queries; an inference detection mechanism configured to perform inference detection using the set of search results for the extracted keywords; an expected-content mechanism configured to determine, from the set of candidate keywords, a set of expected-content keywords which are determined to be representative of the previously sent content based on the inference detection; a ranking mechanism configured to rank the set of candidate keywords extracted from the search results based on a confidence value generated using web-based inference detection, wherein the confidence value evaluates the candidate keyword's sensitivity to expected content; a selection mechanism configured to select one or more top ranked keywords to represent the first piece of outbound content; an inspection mechanism configured to determine whether outbound content is proper in response to receiving a second piece of outbound content, which involves performing one of: determining that the second piece of outbound content is associated with the first destination identifier, and the number of expected-content keywords present in the second piece of outbound content is below a first predetermined threshold; and determining that the second piece of outbound content is not associated with the first destination identifier, and the number of expected-content keywords present in the second piece of outbound content is above a second predetermined threshold; and a display mechanism configured to display the destination identifier for the second piece of outbound content, the selected one or more top ranked keywords to represent the first piece of outbound content, and at least one expected-content keyword selected to represent the second piece of outbound content in response to the second piece of outbound content being improper, thereby allowing a user to determine whether the second piece of outbound content has the proper content and destination identifier. 13. The computer system of claim 12 , wherein while extracting keywords from the first piece of outbound content, the first keyword-extraction mechanism is configured to determine a TF.IDF weight for a respective word or phrase contained in the outbound content.