Nice to hear Crossfire performance is great.
Overall I really like these cards. Definitely looking forward to the 6970/6950 series, although I'm not looking for an upgrade.
I'm very interested to learn more about AMD's Morphological AA. It seems to have some drawbacks (blurring/softening image, even 2D in games), but it also seems to have a very low performance hit. There's a thread about it at the Hardocp forum.
There are comparison screenshots at the last page, and Hardocp will post an article covering Morphological AA soon.