You have to put into perspective that many large companies have a "corporate desktop" with a custom environment built around specific applications and tools- not to mention the adaptations of their network itself.
Microsoft cant even make their web browsers backward compatible and stable (or forward compatible most of the time) and large organizations spend enough just keeping the platform running on a daily basis to worry about migrating to another pointless round of years solving needless hurdles and bugs.
I work for a large company that still uses XP on modern hardware, and before this I worked for another very large company that still used OS/2, Netware, and AS/400's. (And TokenRing, while I'm at it)...
It's not about being trapped in antiquity- its about having a business to run first.
