Account by Lincoln. B. Stein, in Webtechniques.

"Eventually, with this pressure, EVERYONE is going to ditch GIF in favor of PNG. Web folks will stop asking image software vendors to support GIFs, and the software guys won't want to pay the license fees so they'll just stop supporting GIF."

Unisys, the holder of the LZW data compression patent used in GIF formatted graphics, is taking a hardline against intranet and internet web sites by demanding that they acquire licenses. [MIS Guide About.com]

From Slashdot.org. "If you use GIF graphics created with certain freeware programs, your chosen program uses LZW compression to create GIFs without license to use it, you may be violating a Unisys patent."