Just had a chance to watch this, so damn cool...
Apparently in the summer there's many more phones coming with it built-in.
He says they have 7 phones in testing right now (n.b. the vid's from Feb), but he's not allowed to mention makes/models.
Nothing mentioned on their site that I can see, I've emailed them, they'll prolly just say ask Nokia.
Please let there be MHL via 3.5mm* or mUSB or the possibility to "hack it in" later Nokia.**
Don't hold your breathe anyone, but no harm in dreaming

*of course if implemented via 3.5mm, it'd be more limited than mUSB in functionality.
**If they're already a licensee, gradually implementing it after the N9's release, may not be an impossibility.
So long as the boss is cool with employees doing it on company time. Extremely wishful