One reason they fear opening the apps on the phones
Fear of the moment you're able to run custom apps on their phones and can do IM over the internet bypassing their ridiculous SMS charges and/or plans. Even their own supplied AOL, MSN, Yahoo IM client applications are made to use SMS so they can charge you. Worst of all, they double dip as they charge you for the SMS message AND the bandwidth against your Internet allowance.
"Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe." - Albert Einstein
Jose A. Hernandez * System Admin * MPLS, Minnesota, USA *
·Time Warner Cable
Bingo! Assuming you can get "real" data-based IM chats loaded onto a phone, they currently work, at least on AT&T's network. I'm surprised they haven't filtered that traffic yet.
I think it's not really a problem yet, mostly due to the convenience factor.