As is stated in the other thread about this, there are two things...
1. IM is not listed in the T&C's for the 7.50 option, just the PRO version.
2. It is still not sure that when they list IM, they are referring to MSN-type applications, and not push-to-talk or some similiar technology..it seems people are being told different things when they phone up!
I don't know a smartphone/windows mobile user that does not use MSN once in a while, and I am yet to see a post/indication that someone has actually been spanked by T-Mobile for using it, so I guess the abov two points ring true, and we are safe for the moment. The other thing to consider is that T-Mobile ship their phones with MSN installed.
Motorola Tristar > Nokia 8210 > Nokia 8310 > SPV > SPV E100 > C500 > M5000 > Diamond/Victor > Leo/HD2