I have been active in many different forums, and those that allowed image sigs have had a ungood athmosphere there. Especially the animated Avatars and sigs were atrocious. Distracting, annoying, and often in a bad style.
There is a reason why i only browse the web with AdBlock active. Not because of ads per se, but because of all the waving and blinking and flashing and the "Me Me MEE HERE!!!! Look HERE!!! *flash* *blink*"-screams of the animated ads. How anybody can concentratedly read a post with everythig moving around it i cant fathom. Too distracting, when i am on other people's PCs to check something quickly. Baaah.