Interesting development, along with the news that Dell is again offering XP on new machines, 'amid significant customer demand' (CNet 2007).
As for going over to Linux, it's a really interesting experience, even if you're just a general tinkerer. As mentioned above, I'd recommend a second machine, or a dual boot (not as horrible as it sounds).
When I tried Ubuntu and Debian (two different PC's) I really enjoyed learning something new, but you need to 'un-Microsoft' yourself. For instance, you can't just plug a memory stick or portable CD drive into your machine - you've got to learn how to get Linux to mount these devices, then configure it to do so automatically. Again, not as nasty as it sounds, with a little persistence and some good reference material.
Performance is also excellent.
James