Mod parent up.
I used Windows 95 (a step up from 3.11, but took a while to mature) and Windows 98 (fantastic) before I moved to Linux. My parents and friends continued on the bandwagon with Windows ME (disaster), Windows XP (pretty damn good) and Windows Vista (crap). I now have a Windows 7/Debian dual boot system, and it works quite well.
I remember Microsoft just about killed themselves getting Windows 95 done, in reaction to OS/2's stronger than expected showing. They just about had to release something in order to quiet the market down. Early versions were indeed rough, but after 18 months it was much better; who knows what might have happened if they'd waiting that long -- OS/2 might have grabbed significantly more market share.
Windows Vista was the next generation XP .. but missing several of the significant features that ended up going into Windows 7.
If Windows 8 is also going to be used as a mobile platform, it might get some extra testing that will find the Oh, It Broke Out In The Field mistakes. It could be that Microsoft has finally learned their lesson, and won't release according to some Marketdroid's schedule, but rather when the product is cooked and ready for release .. but history suggests otherwise.