Totally agree with what sberlin said, but i would add (if this hasnt been said b4):

- ability to search for a particular filetype (.pdf, .cbr) etc

-ability to rate something as a fake

-ability to cut out a search tearm; for example you might want to search for "star wars", but cut out all entries that have the word "skywalker"

-chatting feature like msn with a "nudge" to alert the user or a sound or just somehting to grab their attention