Last year, on one of my posts I've written that Microsoft would be discontinuing licenses for Windows XP by Jan 31,2008. Eventually, Microsoft changed it's announcement and moved back from what it said before. They've been distributing new licenses ever since and Jan 31,2009 was set due date for expiration of XP License distribution which again was extended. For obvious reason that Vista is still nightmares for many of the old XP users to adopt.
Microsoft has extended the licenses for distribution till May 20,2009. It looks like XP is not going to die pretty soon.

For reminder,support(including patches/security updates) for XP will remain till 2014 as per their announcement.
Personally, I've never felt Vista that ugly as what most of the people have been reporting continually. But, I confess that at some point, I had weird experiences with Vista which I think is not so significant.
Whatever,Windows 7 is ready to hit the market pretty soon and with that, Vista will be dead without even reaching it's maturity. XP really had long years of acceptance and is still favored a lot. This is why, Microsoft was compelled to extend it's expiration date.
Thank you for reading my post.
Comments
As many predicted, it would take some time to adopt Vista as people did when adopting XP but things are going far away to become reality.
I had read leaked news that even before Vista's release, Microsoft were planning their next OS right after Vista, code named 'Vienna' somewhere by the end of 2009.
To me it's 'Windows 7' which they are planning to launch by the end of 2009.
I comprehend yours saying 'New is not always better'. Only few people are aware of these crucial facts.