I just got an iPhone 4, less than a week ago. It’s my first iPhone. As a self-described textaholic, I’ve been having a lot of fun with it.
The only trouble I’ve had texting so far is with MMS and group messaging. If you turn on MMS and group messaging, all group messages will be sent as MMS regardless of whether or not they include photos/video/etc. This is because all the recipients are sent along with each text, so if you send a group text to iPhone users, any replies will go to all of the original recipients.
Cool, right? Usually – but if one of your recipients can’t receive MMS (probably because of their phone’s model) they won’t receive that text at all. Or any replies.
Unless you send texts exclusively to iPhone users, it’s probably safest to turn MMS on and keep group messaging off.