I know someone who is, David. And cost £100 for some 'professional' to install. This being the same 'professional' about a year ago who said that the reason for his PC motherboard acting up (and replaced when not necessary) was because of... (You won't believe this!) ...
"Because his PC is on a earthquake fault line".
(Don't ask! But as he is austistic, he sort of brought into the excuse). Had that been me, I'd have created a fault line courtesy of his head smacking floor!
But otherwise, Windows 7 as I understand is just a polished up version of Vista. (previously 'Longhorn'. Stupid name unless designed for rednecks or something?!).
Vista itself has more security holes in it than a Swiss Cheese from stories I've read over the last week or so. I use XPSP3 and rather the better the devil you know, at least for now.
Although I was far more comfortable with Windows SP2. Slower, yes, but more secure.
Phil.