So I just walked out of a Microsoft Store, (yes, even though there are 14 across the US, I live close to 2 of them. lucky me!)..
And I have confirmed we will indeed be getting the Lumia 800 next week, Feb 14th, it will be available in Black and Cyan, next month other colors (red, green and fuchsia) will be available, and then in April the white Lumia 800 will be available.
The Lumia 800 will be sold unlocked (use with either T-Mobile or At&t), and you have the option to get it as a bundle (Lumia800+Purity Headset+Nokia Play 360 speakers) for $899 or just the phone (between $550 and $600, I couldn't confirm the price yet).
I couldn't get a confirmation for Lumia 900 on March 18th or whether it would come in white, I think they are leaving it up to At&t to announce it (after all, it is exclusive to them!)
I'll keep you posted!
[update] postponed to February 20th