Since word seems to have spread: Regarding the T-Mobile Galaxy S2 (T-989). Yes, I have one and yes, I will be trying to get a stable CM9 build running on it.
Fair warning that this can only be a spare time task for me right now and I have a lot of priority projects right now, so it likely won't be quick. If anyone out there would like to help, that is great - let me know. Otherwise, I will do what I can.
I will update on progress, but please continue to be patient. :-)