My Husband bought computer with Vista preinstalled a couple of months ago. He wanted XP, but the vendor was allowed to offer only Vista, and told that it is not hard to get accustomed to a Vista machine. It is not hard, if you want it to be a toy.
Here are his impressions (I never touch this thing, don`t like it):
1. Hardware - Vista requires a lot of resources. It doesn`t work smoothly with 4 GB RAM installed.
2. Looks - pretty, if you go for it. He doesn`t. I`m the proof.
3. OS stability - it is harder to mess with system settings.
Finally: he doesn`t like Vista. If he wants to do some serious work, he sneeks to my 6 yrs old, 256 MB RAM, XP3 laptop. It is just more comfortable.
I talked to some friends in IT industry. Generally, they agree:
- MS has invested some big money in Vista, and has limited time to return it, because they will soon (next year ?) release Windows 7. They need to dump XP, and what Ballmer is talking can be called "damage control". They hope we will gradually accept Vista.
- XP is designed to work on any HW configuration, and leave as much as possible resources to applications. Vista is designed to provides for itself first, and what`s left can be used by other applications.
- Second reason Vista requires so much resources is the idea to be frequently in touch with Microsoft and report about users habits and preferences (yup! sounds like spyware).
- Companies and US Government still use XP. To switch on Vista, they must invest in new HW, because what they currently have cannot support Vista. Some companies have hundreds, or thousands XP machines, so do some calculations.
- Environment - how can we safely dispose so many good, yet obsolete computers in next two years?
- Besides HW, here`s also a SW problem. Business applications are often created for specific type of work, or even for a single (medium or big) company. Costs for SW upgrades will be at least 10 times bigger than expenditures on HW.
- Here should be added costs for extra work hours, staff education, time for transition on new HW/SW, time to establish information reliability (they will probably work parallel on both systems), etc, etc.
It will be interesting to watch Microsoft getting out of the hole they dig for themselves.
Crazy idea: Apple bought Microsoft and forgot to tell us about it?

Reason for editing: broken language I call "english".