its not being rushed out, like people before mentioned its being updated as we speak, unlike previous versions of M$ Os', there are no Major releases in the beta schedule.. no "Beta 2, 3 etc" they are just constantly revising in small amounts and through live updates. so its not a rush out its actually just a more gradual process.
And yup it seems considerably better than vista overall - I personally liked vista and had little issues running the 64bit version (once all the drivers were properly released) but Windows 7 seems like Vista SP1 already (a bit snappier to navigate too).
Cheers
ROfu