go to the upgrade section for the 7290, there is an instant messenger upgrade that included MSN Messenger. Meant for the 7290 but works perfectly on the 7100T. Use application loader to install on your device.
it also uses messages from your text messaging pool, as well.
berryvine is an msn messenger IM client that is free, i believe... but its crap.
I was told by a T-Mobiel network engineer that it does not use your text messaging pool... I have not been able to confirm this but I should find out before I got over.
trust me, it DOES use your text messaging pool. i can guarantee you this. its an SMS-based messaging application. the BlackBerry has the ability to do SMS-over-GPRS (SMS over data network) to bypass the text messaging usage, however, T-Mobile disabled this some time ago - for 'billing' purposes (per TMO customer service rep).
corey, you serious? just in case (and no, it won't work with non-TMO, so your Rogers phone is out of question)...
Yes, the TMO application for the 7290 also works for the 7100T. I use it right now. I'm not sure why they wouldn't just give it also to the 1700T. Is my phone going to blow or something?