I'll say it again
..as the hype machine tries to pick up speed.
Most of the large sites I've worked on recently are running XP with security patches which are several years old. Instead they rely on security software to do the job for them. Now, some people may not think this is a good solution but on the other hand none of them have had any security problems.
So, for companies like this, there's no hurry to upgrade which is probably why lots of them aren't doing it.