Nokia is porting Qt, the results of which are available right now in Extras. But for Fremantle Qt will only be community supported, the official support will come with Harmattan. This means a Qt Garage project and distribution through Extras (much like Python).
Unfinished how, exactly? Are you referring to the example Clutter UIs available or the actual toolkit? Either way, recall that this is only a pre-alpha.
I didn't make a differentiation because it isn't relevant here. They've got somewhere in the ballpark of 6 months to polish it up and move it to Extras. Give it time.
From your questions, it sounds like you're more of an application developer, so you're gonna want to wait for a later alpha release or the beta release around March-May.