1. A method for categorizing network traffic content, comprising: receiving, via a network interface device of a networked device on which the method is implemented through instructions executable by at least one processor, network traffic content including an electronic message; determining, through execution of instructions of an electronic message content categorization module on the at least one processor, a first characterization of the network traffic content, the first characterization including that the electronic message likely includes undesirable content, the determining performed according to at least one analysis technique to obtain at least one categorization of the electronic message indicating the electronic message likely includes undesirable content, the at least one analysis performed as a function of a database of known categorization properties of electronic message content; determining a first probability of accuracy associated with the first characterization; categorizing the network traffic content based at least in part on the first characterization and the first probability of accuracy; and storing, on a data storage device, by the electronic message content categorization module, a representation of the determination that the electronic message likely includes undesirable content and data derived from the electronic message such that the stored representation is available to assist in processing subsequently received electronic messages included in network traffic content.