I make a lot of GIFs for my tributes. I like that they will display for people without them needing anything more than just a browser. Often, movies require some sort of plug-in or QuckTime or Flash viewer or extension that is insecure, etc. Animated GIFs normally display fine directly in any browser.
I certainly understand that some of them are not well-crafted, but in general, I really enjoy most of them. I do wish people would get their orientation and aspect ratios correct, and there are some that display with odd artifacts, etc. But the vast majority of them are enjoyable for me.
So chalk up one vote in favor of animated GIFs both as a "content contributor" and as a "content consumer".
I work hard to make the GIFs I create. They're not easy, and require a lot of computing power to run Photoshop making them because of the huge number of frames that a snippet of video often entails. And I appreciate the work other folks must be putting into making theirs - either as original content or as captures from great porn videos.
To each, his or her own, I guess. They are a LOT smaller than videos, in general. And when done well, they can convey a brief interval that is particularly hot. Anyhow, I, for one, like them.