I got my HD-DVD for the 360 today, they still had a lot in stock in a local shop here. Oz bought one last week, and told us that they still have a lot in stock. So a friend went there to buy one the weekend, and I asked him, to get also one for me. So I got it today, price was 9.95€ , not that I really need it, but it's always cool to have.
Big plus is, that it comes with the 360 remote control, and it can also be connected to a PC like a normal USB drive. And when I look at the films that are available for HD-DVD, wow, they are really cheap.
And in case you didn't know, HD-DVD movies also contain the normal DVD version which can be played on any DVD player. So if you want to buy a film, buy it on HD-DVD, it's cheaper than the normal DVD, and you'll have it in both formats.