For the most part this doesn't seem like a bad a driver; there's some really good updates in it and there's no negative performance for the most part. Performance is a little wobbly in some areas where we see the minimum drop a little and the average slightly increase, but it's nothing that we'd be all that worried about.
ATI has also promised some more performance gains for CFX users and this is good news for the next generation of cards coming from ATI later in the year. If they can gain some ground on NVIDIA and its SLI technology in the next few months, they'll really be able to offer some competitive products, because at the moment SLI remains the better technology as it just scales better.
In saying that, I've already read that people have had issues with the driver set. After installs people are getting BSODs and other things like that; but because we all have a different machine it could be so many things, so it's worth making sure you've got a restore point set before you go ahead. Just in case you run into some real dramas, you can roll back to what you're currently using, which for most people is the 10.4a or 10.5 driver.
Until next month, may all your frame rates be high and your games good fun!