As a Vista power user, I can say without any doubt that if you ever experienced any problems with Vista (I never did), it was because your computer was outdated and not up to snuff (and I really pity the people that bought a laptop from lets just generalize.... Best Buy or WoolMart, that came preloaded with Vista on a rig that was never intended to be able to really run Vista. Those minimum operating specs are the minimum it took to load Vista, not the minimum to load it AND run any sort of softs on it).
That said, 7 is without a doubt the most elegant and user friendly OS I have ever had the pleasure of working with. If Apple had a marketing scheme other than "WIndows is the bad guy, so you should buy us" they could learn a lot about not sucking from Windows 7.