I work with small businesses, and the upgrade to Win7 is just under way with 64bit snags. A lot of small shops run their business on some little db app.
If it's QuickBooks, the pain is reduced as Inuit wants you to buy a new version each year anyway.
But if it is a application targeted toward managing something like a law office, veterinary practice, etc. I can tell you it's very common for the application hasn't been ported to 64-bit yet or the owner hasn't ponied up for the new major point upgrade. With the economy in neutral, expenditures are conservative in small businesses.
Beyond that, the end users really, really dislike change. Even the minor changes to Office '7-10 or Win7 get push back. Mostly these people don't want to screw something up because they're unsure of proper new way to do an old task. Some of it is also frustration at just wanting to get their work done. Once they get it sorted, it's OK - but, when picking the replacement I am usually told to get the old familiar not the new hotness.
I don't have strong opinions on Win8. However, I am paid to make people productive. Neither me nor my bosses get paid to push new because it's new. If there isn't major advantage to the new version is will ramp up slowly. cf. WinXP. The consumer market may go crazy, but if I had to guess most of those people just want a tablet that's priced entry ipad or less right now.