You will have to hunt for XP copies on the net. Retail stores won't carry them (on sale at Newegg until 3/15; after that??) and you won't be able to buy a new computer with XP. One poster said Best Buy last week wouldn't sell him a computer with XP even though it was before the Vista rollout date. You're correct about the support being around for at least five and I've read seven years.
Well, If you have XP Pro now... you can transfer it... whats the problem?
I would be the typical consumer.
Meaning I have basic knowledge of computers and systems. There are lots of people who know less than me.
My point is, your basic consumer which makes up 90% of the computer owners don't care which system or how much ram of this or that.
Microsoft lives off the basic consumer so it is in their best interest to make everything work easily to the digitally impaired. If they didn't do that, they would rely on the 10% that know what they are doing.
They are not going to get rich off 10%. Therefore I am not too awfull worried about it.