So it appears that the link to start downloading iTunes 10 is now working.

At least for now it seems to work if you use Safari, but you should use this link:

https://www.apple.com/itunes/download/

I just tried the link with Mozilla Firefox and it is still showing coming soon. So if you want to get it right away use, Safari and it will display the right page for the downloading of iTunes 10, from Apple released today.