iPhone 4S pre-order: What to know before you buy

The iPhone 4S pre-order line starts now. But before you pull out that credit card, there are a few questions that you need to ask yourself.

At just past midnight on Friday morning, Apple officially made the iPhone 4S available for pre-order, and according to one source, for a few hours, "both Apple and AT&T servers were quickly hammered into oblivion." Which makes sense: Despite the chorus of downer quotes from disappointed analysts and fans, an iPhone launch is still a major event, capable of stirring up a sandstorm of interest across the Web.

So what do you need to know about the iPhone 4S pre-order frenzy?

Well, for one, this is the first iPhone to launch on three separate carriers. Verizon and AT&T both get the device, and so too (as predicted) does newcomer Sprint, which is offering consumers an incentive – the option to sign up for an unlimited data plan. (In the past, both AT&T and Verizon offered similar plans, but new customers at both of those carriers no longer qualify; others can be grandfathered in.)

Also new is a 64 GB iPhone 4S, which will sell for $399. (All three carriers sell the 16 GB iPhone 4S for $199, with contract, and the 32 GB iPhone for $299, also with a contract.) Obviously, that's a whopping amount of storage, with a whopping price-tag to match. And over at CNET, Scott Stein ponders whether the increased capacity is really worth the extra dough.

"I actually enjoyed using a 60GB iPod years ago because it was the only size that fit my entire music library," Stein writes. "No flash iPhone ever reached that same storage capacity. Now that one has, I am also wondering how much cloud music or iCloud services will result in needing less storage space."

Of course, if you're not pining for the iPhone 4S, it's worth noting that Apple has dropped the prices on all of last year's iPhone 4 models. So you can get the base model iPhone 4, with 8 GB of memory, for $99, or the 16 GB iPhone 4 for $149.99, or the 32 GB iPhone 4 for $199.99. And don't forget: the iPhone 3GS is now free. (All those prices are contingent upon the signing of a two-year contract, so plan accordingly. Spending $80 a month costs a lot more than the initial price tag would suggest.)

Finally, a word to the wise: Although it can be great fun to stand outside your local Apple store with the rest of the neighborhood Apple fanatics, it can be equally fun to pre-order the iPhone, have it shipped to your house, and wait comfortably on the couch until it arrives. Just saying.

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