It is essentially Vista, but rather what Vista should have been from the start. In the sense that it's much quicker, more stable and generally nice to work with.
When you give it a try you'll be pleasantly surprised.
Out of curiosity, what linux distro are you using?
I would have agreed with you before trying the beta, but it's clear from its quality that there has been some serious changes happening over at Microsoft. Since install it's worked fine for me, much better than Vista when it was initially released.
I'm quite confident that Windows 7 will put them on track again and from the state of the beta, I'd say they are pretty close.