Thought I chip in too as I've been lurking around these parts for a couple of months (mostly checking on the progress of the iMac issues as that's what I was looking at buying). Sorry, it's a bit of a long post.
Around September last year I decided I wanted to have a go at iPhone development so could only do that using a Mac. I didn't want to spend lots of money straight away so firstly went down the route of getting OSX running in a VM ware image, that worked and I was able to try my hand at coding in the iPhone SDK to see if it was worth investing money. Having done that I reaised that going down the virtualisation or hackintosh route was just to complicated, the trade-offs and issues just made the experience more trouble than it was worth so I decided to spend some cash.
The first issue was finding a suitable replacement for my PC. Having been a Windows Sys Admin, Unix Sys Admin, support person, developer etc... I've become a bit of a tinkerer so like building my own systems and changing things reguarly so the thought of being locked down wasn't good. However with my wife always complaining about the noise my PC makes I decided I could cope with giving that side up for a nice quiet cable free desk. So what to buy, I didn't want a laptop, mainly because I didn't need it to be portable but also, well, have you seen the prices of the top end models! A mac pro was out of the question too, although it's upgradeable I didn't really need a Xeon processor (or 2!) and, well, have you seen the price of those too! Mac minis, a little to underspecced, so that left the iMac and because I didn't want to go lower than the spec of my own built PC I decided on the i7.
....Oh dear, finally made my decision and then I read about the long list of issues with the iMac. Decided to pop along to the nearest apple store to actually have a look at the machines to see if I could spot some of the problems and had my first experiences with the staff. To be honest I was fine with the dress sense and everything, it's what I was expecting, but what I hated was being labelled a 'switcher'. There seemed to be no understanding that someone could be just as happy to use Windows as they are to use OSX, they'd already decided that if I bought a Mac I'd eventually decide that OSX was all I'd want to use and I found the whole 'Mac is the only way to go' attitude the biggest gripe I had with them.
After this lengthy decision process and then subsequent weeks of lurking around places like this I decided to order an i7 online. I did so on the 25th of Feb and as I'm in the UK got ready for the two week shipping wait.....to my surprise my week 9 model left Shanghai on the 27th and was delivered by UPS on the 4th, exactly a week later. I powered it up and it was perfect, I couldn't find any faults with it. The first thing I did was install Windows 7 via bootcamp and that went smoothly too.
So after only ever owning PCs....I love the iMac, as a package it looks good, runs silent and My desk now has a lot less clutter so I'm very happy with it. As far as OSX vs Windows, well I don't really care, they both do their job and I use whichever is appropriate for the task I'm doing. The buying process, well I don't like the limited choice of models and the fact that there isn't a decent PC equivalent sat between the iMac and the Mac Pro, and I could do without the 'Apple superiority' attitude that seems to exist in the stores, but buying online was great and at least the stores have almost all the models on show I can play with properly, I just need a 'do not disturb' sign!
So if anyone else is contemplating it, I can fully recommend the i7 iMac and if you like windows, you don't have to leave it behind......I'm only left with one real annoyance, if Steve Jobs would just let me run OSX on a PC (theres no technical reason why it can't) I could have saved a lot of money.