My wife needs a new cell phone. She's never had a smart phone, and normally wouldn't care for one, but she's gotten used to Android (CyanogenMod 9) on her HP Touchpad, and could benefit from having the cloud sync for calendar/contacts/etc. I wouldn't expect she'd be a heavy data user, so T-Mobile's limited data plans seem to be a more cost-effective option than Sprint's (my current carrier's) "unlimited data, but it'll cost you" option. Plus Sprint's family plan discount is really weak.

So, I'm looking for an Android phone that meets as many of the following requirements as possible:

1. Physical keyboard with landscape orientation (slider/flip)
2. Usable on T-Mobile
3. Can be loaded with CyanogenMod (prefer 9, will accept 7 if 9 isn't ready)
4. 4G would be nice, but isn't necessary

I don't see anything in T-Mobile's current lineup that's in CyanogenMod's official support list, so I think this means either buying an older T-Mobile phone or buying something unlocked. Any suggestions?