Pretty much as the title says, using bootcamp.
WDDM1.1 compliance and GPU recognition confirmed by the WP7 emulator running with EnableFrameRateCounters showing.
I'm considering a Macbook air as a compromise to resolve a need to access iphone dev tools and upgrade my Win7 mobile capability to something reasonably performant with one device.
My current laptop barely runs Win7 and borders on unusable for WP7 tooling hence the interest to try and solve two problems with one device - if realistic.
I assume if the device can run WP7 tools satisfactorily, it would be capable of anything else I might want to do when booted under Win7.
The new MacBook Airs do not have very powerful processors. The 11" maxes at 1.66 Ghz, while the 13" maxes at 2.13 Ghz. However, they do have the same GPU as the current 13" MacBook Pro. Also, since they use solid state drives, data access is significantly faster. Overall, it will not be the fastest computer you've used, but it should be enough to work.
I've bought one, but since it's going to the wife, I won't be able to test it in depth.
Instead, the MacbookPro 13" from '09 works fine (monoTouch+iOS dev and bootcamp to vstudio+wp7 dev). I upgraded to 4 gigs memory and that helped, also the disk is slower than I'd like. It responds like a mid-grade desktop, imo.
The problem I see is that the processor on the air's is ULV with a really slow clock, also the sdd in the base version is only 64g which is going to be cramped, I think.
Consider this: many Mac gamers install Windows with bootcamp just to have better gameplay experience.
That's because Windows have native access to the GPU through bootcamp.
http://www.mth.kcl.ac.uk/~shaww/web_page/grid/macgpu.htm (2009 article)
http://www.gpgpu.org/forums/viewtopic.php?t=3766&highlight=bootcamp (2007 article)
So the answer is yes.