The iPhone 3G is coming to Canada this month, and Rogers posted its iPhone rate plans last week. As Richard (among many others) notes, unlimited data — taken for granted on U.S. iPhones and other smartphones — is nowhere to be seen. Data caps range from 400 MB to 2 GB, with overages costing 50¢/MB for the first 60 MB, then 3¢/MB after that. This has caused a considerable uproar, including an online petition site that has since gone 404.

Not everyone who wants unlimited data wants to use it in an unlimited fashion; indeed, I would imagine that the majority of Rogers subscribers will not exceed the data caps. The problem is, people imagine that they could, and worry what would happen if they did. It’s easy to avoid exceeding your monthly minutes: you call less. But data is charged by the megabyte, not the minute: when you check your mail, you don’t know if someone just sent you a 20-MB attachment or if you’re downloading a pile of spam; you don’t know how much bandwidth you’re using when you download a single page. You don’t have the same direct control over your data usage as you do over your voice usage.

In practical terms, this means that consumers who pay for their own smartphones (as opposed to corporate customers, whose employers will pay the overages and who I have long felt the Canadian mobile phone companies really want to do business with) will either pay for more data than they need, or use less than they’re entitled to. Which suits mobile phone companies just fine: they’re in it to make money, as they should; and they have an interest in not clogging their voice and data networks. But it makes an iPhone that much less appealing to consumers. (For example: Google Maps pages are huge — how many times can you look something up on the map at 400 MB a month? And that’s just maps.)

Bottom line: I’m still happy with my iPod touch. (Not that I was a likely candidate for an iPhone in any event: Rogers’s signal is too poor out here, as I learned as a former Rogers customer, and I’m not often away from a connected computer or a WiFi network. Also, I’m highly averse to monthly bills. Still.)