Hey Dude, the messaging package for the iphone is the same one for all AT&T pda plans. It does not designate only SMS. It includes any form of text, whether SMS or MMS. If the phone can handle MMS, the plan includes it. The iPhone is the ONLY phone I know of that doesn't support MMS.
Email may be fine for pictures, but MMS supports so much more. What about video clips, audio clips, Real media, Windows media, etc. Probably the only reason the iPhone doesn't have MMS is because it doesn't support the files needed for MMS. Apple only wants us to be able to use the files THEY want us to use. If it's not Quicktime and comes from iTunes, which involves revenue, then forget it.
I have been pondering whether to upgrade to the iPhone 3G. But, considering the lack of MMS and a lot of other features of most other phones or pda's coupled with having a new two year contract with higher fees, I am seriously considering changing to another device.