Can I buy the iPhone 5 without a contract?
It's not clear at this time whether or not Apple will offer to sell the iPhone 5 unlocked, as they did with some previous models.
One of the technical questions that might prevent unlocked, out of contract iPhone 5 sales is the fact that three different models have been produced to ensure LTE compatibility across different networks worldwide.
In the past, the iPhone has been available with no contract for an additional $400 above the subsidized carrier price. We will be watching Apple carefully to see if they begin to offer the iPhone 5 without a contract in the future.
UPDATE: Both AT&T and Verizon offer the iPhone 5 at full retail price with no contract when ordering on their websites. Verizon has an option to show pricing for "Month-to-Month" while AT&T allows customers to select "No Commitment".
UPDATE: T-Mobile is now offering the iPhone 5 (starting April 12th) contract free for $579 ($99 down and $20 a month for 24 months).