I still remember my first 3D card—the ATI Rage Pro—so it's with great sadness that I'm writing this: AMD has officially killed the ATI brand. OK, I lied. I really don't give a damn.
AMD has decided to kill the ATI brand after a study showed that most people don't care much about it:
1) AMD brand preference triples when the person surveyed is aware of the ATI-AMD merger.
2) The AMD brand is viewed as stronger than ATI when compared to graphics competitors (presumably NVIDIA).
3) The Radeon and Fire Pro brands themselves (without ATI being attached to them) are very high as is.
From now on, it's only Radeon and Fire Pro:
The first non-ATI graphic AMD cards will be released later this year, but even the Wikipedia page has been updated with the news, showing ATI as "defunct" on August 30, 2010. [Techreport and Anandtech]