The process to enable MMS is simple. Make sure iTunes is version 7.7 or later and that the iPhone is 3G or 3GS with iPhone OS 2.0 or later. Connect your iPhone to your computer and you will be prompted to update your carrier settings. If you are not prompted, choose your iPhone in iTunes, hit the “Summary” tab, and hit the “Check for Update” button. The update is quick and you will have to restart the iPhone.

After the update is installed, a camera icon will appear next to the text field in the Messages app.

iPhone users can send an MMS to any phones that have MMS enabled. MMS messages count against iPhone texting plans, so there will not be another fee to use this feature.

MMS sending has improved for me since launch day. Previously sending an MMS would stall and it would have to be resent a few times. I was not able to test a video MMS because I own a iPhone 3G.

The big reason why AT&T delayed the iPhone MMS launch is concerns about how their network would hold up. With the popularity of the iPhone, AT&T was concerned these users would bog things down. Other phones on the AT&T network have had MMS enabled for a long time, but iPhone users will theoretically be using MMS far more. iPhone users on other networks have been able to use MMS since day one.

Building a network is costly, but iPhone customers should not be treated like second-class citizens when they are trying to use their “unlimited data” plans. iPhone customers are paying high monthly bills and should not have to deal with this.

One more thing AT&T: where is tethering?