The ATT MMS rollout will begin on the East Coast at 10am and roll west hourly as long as ATT servers hold up. Whether they will hold up remains to be seen, there were problems with the testers.
You’ll receive a text from ATT informing you that MMS is now working on your phone. ATT also said you’d need to do an update through iTunes to install the new carrier file.
Some cities are getting it before others and people with family texting plans rather than iPhone texting plans are getting it sooner.
Some people are running 3.0, some 3.1, carrier files are 5.0 and 5.1. There are directions to obtain and install carrier file 5.1 on the forum, but it seems to be switches on ATT’s end not carrier or Apple files that are making the difference.
If you go to settings, messages and only see two options on your phone, it’s not on for you yet.
But the 25th is coming soon, so keep checking your phone and it won’t be long.