I'm pretty impressed. Aside from temperature and the imminent power needs, it seems like the R700 soundly trounces the GTX 280 by at least 25% in almost everything (Crysis excluded of course). But then again, ATI cards have almost always been very hot and power hungry, yet still handle it very well, and no one's really complained about it much in the past.
Factor in that this is an ES, there's still better drivers to come, factory OC's, custom coolers, etc, etc. and I could see things just getting better and better.