Why do you say that? Since the 2.3 release, there has been a skybox issue affect ATI users. I know Josh has submitting an issue with ATI to fix this, but it still exists.
Until hardware released issues are fixed and an offical game/app has been published, then your words may ring true.
Plus, if anyone did publish anything with LE, they still will have an issue with ATI users running thier applications. Even with 2.2#, I did notice some of the demos had rendering issues (maybe an ATI issue as well). I did not report them because I assumed they were already.
I'm not bashing LE, because Josh has did an amazing job based on what I have seen. I am looking forward to using the same engine as nvidia users.