doesnt run win7, but theres a chance it will run win8. probably wont run it well, but shit the entire pc will cost less then the oem license for the software
Really doubtful that there's even a chance, as the ARM core in the chip is a v6 and Win 8 apparently requires at least a v7. Additionally, the 256MB of RAM in this Pi (which includes the frame buffer) is _really_ unlikely enough to even boot Win 8.
A potential future version of the Pi, fitted out with one of the more advanced Broadcom VideoCore chips (BCM21654 or BCM28150) almost certainly would (assuming someone does a port of Win 8 to it) if it was configured with enough memory, but you're likely talking about a much more expensive gadget than this Pi... (And that's before, as you mention, you even get to the Windows license costs.)
However, I'd think this would make quite a good HTPC (with the emphasis on HT rather than PC - it won't be a great game machine and I wouldn't do number crunching on it, but it should do HD video display and web browsing fine). The fact that XBMC has already been demonstrated running well on it even though most of the codecs haven't been optimized for it yet seems like a good sign...