Maybe someone can tell me different, but I see the new iMessage feature as completely useless for me.

Apple’s description touts it this way:

If you’re a texter, you’ll love Messages on iPhone. Now it comes with iMessage, a new service that’s even better than texting. Because it’s between you and anyone using an iPhone, iPad, or iPod touch with iOS 5. And it’s unlimited.* So say as much as you want. And say way more.

The asterisk leads to this:

*Normal carrier data rates may apply. Messages may be sent as SMS when iMessage is unavailable; carrier messaging fees apply.

Image from Apple's iMessage page

Here’s the thing. I already have an unlimited texting plan from AT&T that covers everyone in my family. I don’t, however, have an unlimited data plan, so this looks like something that will eat away at my monthly data allotment while giving me virtually nothing in return.

Other people might find it useful. If most of the texting you do is with other iPhone users, maybe you could get by with a minimal SMS plan from your carrier and rely on iMessage. I can see where maybe a young family or an empty-nester couple could save some money this way.

But if you have kids, especially daughters, with mobile phones, you are almost certainly going to have an unlimited texting plan as a defensive measure. Their friends will have all kinds of different phones, so there’s no way to guarantee that most of the texting is iPhone-to-iPhone. And “unlimited” is the only number big enough to encompass the amount of texting a teenaged girl can do in a month. Once you’re on an unlimited texting plan, you want all your texts going through that pipe instead of the 3G data pipe.

If iMessage offered significant extra features, I might see some value in it. Allowing a conversation to jump between an iPhone and an iPad, is a nice feature, but since I don’t have an iPad, it means nothing to me. And though I have sometimes wondered whether a text got through, delivery receipts aren’t that important to me.

The upshot is that I’ve turned iMessage off. It was fun to see who was blue and who was green in the first couple of days after the iOS 5 upgrade, but now I’m keeping everyone green.

Update 10/16/11
I confess to overstating my case a bit. Text is compact, and it’s likely that a good percentage of messages would be sent over WiFi with cost to my data plan. Still, I’m not sure that iMessage messages, text or photo, are as compact as standard SMS messages, so a direct comparison using message count only may not be apt.

I got a laugh from this reply on Twitter:

@drdrang For the record, I have trouble believing that even a teenage girl’s texting volumes will significantly eat into your data plan.

10:26 PM Sat Oct 15, 2011

I had a hard time believing that, too, but experience shows that a 14-year-old girl can run through 10,000 messages in a month without breaking a sweat. Just you wait. Now it’s true that if those are all text, that’s still only a megabyte or so, but as I said, I don’t know enough about iMessage to know how much metadata is being sent along with the message text or how much bigger iMessage photos are than regular SMS photos.

(Keep in mind, too, that I’m a few years out of date on this. The texting capabilities of 14-year-old girls are evolving at a pace almost too fast for science to track. It may be that the 100,000 texts/month barrier has already been breached.)

My point—possibly not as clear as it would have been had I not written this post late on a Saturday after a couple of Harp Lagers—was not so much that iMessage would add a huge load to my family’s data usage, but that whatever increase in 3G use it creates would come with virtually no benefit to us. Your mileage, as they say, may vary, and I’m not suggesting iMessage is a mistake.

iMessage reminds me of Automator. Many people sing the praises of Automator, while I find it pretty much useless. Too slow and too limited, even when compared to AppleScript, which I’m not fond of, either. But I’m not mounting a campaign to rid the world of Automator—if you’re happy with it, good for you. I won’t try to tell you’re wrong.

I wouldn’t be surprised to see iMessage grow as time goes on. Apple often releases software that starts out with limited features and improves significantly in subsequent editions. If that’s what happens to iMessage, I’ll be happy to switch over to it.