Why now? For one, the first generation of artists born and raised on the Web is just coming of age. For those people, animated .gif's aren't just the stuff or Internet cheese, but also a sentimental thing, with all sorts of connotations to beloved, bygone bits of technology.
These artists don't revolve around galleries. Their stuff lives in the wild, on the net, at places like Rhizome , 8-Bit Today , and Internet "surfing clubs"  like Nasty Nets , which are basically club houses for net artists that are almost incomprehensible to outsiders.
Here's four GIF-ted artists we love:
Michael Bell-Smith  is about as close to a veteran net artist as you can get, having shown works at big-time places such as the New Museum in New York:
Harking back to the days of online, Web chat handles, many net artists go by fake names. Videogramo, AKA Francoise Gamma, is a Spanish artist obsessed with the faded look of 1980s cyberpunk classics such as Blade Runner, and you can see it in his art. His sprawling, disorienting Web site  isn't really a Web site, as much as a curated, online gallery:
Like a lot of net artists, Out_4_Pizza , AKA Laura Brothers, constantly revives old-school, 8-bit aesthetics in her work--basically, a way of making the drawings look aged, in a way that's sometimes impossible on the Web. But her art takes that into the realm of goth--always a popular subject for artists raised in the 1980s and 1990s:
Finally, some works by artist/designer David Ope :
For more by all artists, check out the links above.
For another brilliant type of Net art, check out our recent slideshow of images culled from Google Street View , by artist Jon Rafman.