>>1
An image macro is a picture whose portrayed events fit a situation that comes up in coversation. Photoshopped onto it, in 48 point bold Impact font with a 5-pixel border, is a catchphrase that removes all ambiguity of what message the image is meant to get across.
The best image macros don't even need the text to convey their message, and the text merely serves as a vehicle to drive the point home.
Simply photoshopping text onto an image does not make a successful image macro. It has to fit correctly.
And image macros are designed to be REPLIES to a previous post in a forum, NOT as threadstarters; because if you start a thread with an image macro, who are you talking to? Who is the target of the message you are trying to convey?
Image macros, when executed properly, can be considered art. Image macros made by people like Freehaven are considered shit because he sits there and prefabricates them, thinking that he is a Witty Willard by coming up with a library of shitty image macros that have no purpose. The best macros are for one-time-use and should be completely unexpected. See:
http://img54.echo.cx/img54/5103/cunningplan4hr.jpg