Pre-orders for the newly released iPhone 4S began on Friday. Have you placed your order yet?

Following Apple's announcement on Oct. 4, an online buyer-seller marketplace called Gazelle said they received over 5,000 selling orders from people wanting to get rid of their used iPhones. Still, it is hard to determine whether these resale numbers mean the 4S will sell well.

iPhone 4S will hit the stores on Oct. 14, but there was a bit of a surprise Apple left out at Tuesday's event. Unlocked versions of iPhone 4S were discovered on the site on Friday morning, the same day pre-orders for iPhone 4S began. Rather than signing on to a contract with AT&T, Verizon, or Sprint, buyers can now order an unlocked 4S that will be available starting November. The unlocked iPhone costs up to $649 for the 16GB, $749 for the 32GB, and $849 for the 64GB. This might be more worth it for frequent travelers to avoid roaming U.S. charges while abroad, but the prices are still pretty steep.

Although the 4S was met with criticism and disappointment when announced, analysts are saying that it should sell up to 25 million this quarter. Aside from all the new features and upgrades we've all been reading about, Sprint is also going to join the list of carriers with this iPhone. With wider coverage, sales might just do fine. Especially with the unfortunate lost of Steve Jobs last week, everyone will be keeping a close eye on how purchasers and sales are reacting to the new smartphone.