Something else to consider when comparing any version of Windows with OS X is the feeling that you always get (well, I certainly do) after a few months that Windows is starting to get bloated and you feel the need to wipe the hard drive and start again with a fresh install.
At work I was given a new Dell laptop last november (I develop software in .Net for my sins!) and here we are in May and it's had that much crap installed that already I'm wishing I could start over. Yet at home I have a 2 year old 20" core duo iMac that feels as fresh as the day I unwrapped it and considering you can get an iMac that's a lot faster and considerably cheaper than the £1600 I paid, I still feel it was worth every penny.
At work I was given a new Dell laptop last november (I develop software in .Net for my sins!) and here we are in May and it's had that much crap installed that already I'm wishing I could start over. Yet at home I have a 2 year old 20" core duo iMac that feels as fresh as the day I unwrapped it and considering you can get an iMac that's a lot faster and considerably cheaper than the £1600 I paid, I still feel it was worth every penny.