When will the next generation of Apple iPhone, iPhone 5, be launched? Although Apple's next-generation smartphone is not yet officially announced, new rumors have emerged suggesting that an early October release was likely.

Best Buy employees have been informed that preorders for the iPhone 5 will begin this week in time for a release in the first week of October.

A Best Buy source released a document to BGR.com, which shows that the store is anticipating the pre-sales and also that Sprint will be carrying the iPhone 5 at the launch of the new device.

However, Best Buy did note that Apple product introduction and launch dates are subject to change, BGR reported.

Deutsche Telekom AG (DTE) is now taking customer reservations for the next-generation of Apple Inc.'s iPhone 5 starting Sept. 5, as new evidence supports rumors that the iPhone 5, expected to be revealed in October.

Mean while, 9to5mac.com reported that Apple has begun iOS 5 and iCloud training with retail store employees to coincide with the iPhone 5′s unveiling.

The site points out that Apple Stores usually begin their training of new software in the couple of weeks leading up to a respective product launch (obviously this time around could be different, though). Apple beginning their iOS 5 training within the last few days could mean a launch sooner than the recently rumored dates of mid-to-late October.

There have also been reports that the iPhone 5 is going into production overseas this week. If that is so, this could go right in line with the Best Buy early October release date.

Unconfirmed reports say Apple's Chinese subcontractors Foxconn Technology and Pegatron Technology have started production of the iPhone 5.

According to a Japanese IT news site, Macotakara's danbo, the two Chinese OEM manufacturers have begun production of the hotly anticipated device. The report added, however, that since Apple's new operating system, iOS 5, is not yet ready to install, the assembled iPhone seems to be stocked without packaging.

Meanwhile, iPhone 5 release date rumors, as well as speculation over its specifications, are gaining momentum in the United States.

Here are the most rumored features of Apple iPhone 5:

Design: The new phone is expected to adopt a teardrop design that is supposed to be slimmer and lighter than past iPhone models. The iPhone 5 is expected to come with an aluminum plate casing rather than the current glass backing.

Display: The iPhone 5 is anticipated to have an edge-to-edge 4-inch retina display. A curved glass display screen is also rumored that may offer more privacy while viewing in public areas. The Quantum Dot LED technology could be a possible delivery system for the iPhone 5. The new technology needs less power consumption while delivering the same quality of an OLED screen.

Dual-Core Processor: Several of Apple's rivals, from LG and Motorola to Samsung have already released dual-core processor phones. According to a recent media report from 9to5 Mac, Apple gave its developers a dual-core iPhone 4 to allow them to prep for the iPhone 5.

Upgraded Camera: This is another one that will likely happen. In the tech world, a 5 megapixel camera seems passé - as sad as that might sound to some - it's true. Like the dual core processor, several of iPhone's competitors in the Android world have phones with 8 megapixel cameras. A rumor back in April, from Ming-Chi Kuo of Concord Securities, said the iPhone 5 would carry the 8 megapixel rear camera. Another rumor had Sony replacing Omnivsion and making the iPhone 5's improved camera. Expect a better phone with the iPhone 5.

4G: There have been a lot of rumors regarding the possibility of the next-generation iPhone being available on 4G networks for AT&T, Verizon and Sprint. The consensus from analysts and tech experts seems to be that the iPhone 5 will not have 4G support. Our question is why not? Plenty of new phones have come out with 4G, and all three major U.S. carriers are pumping up support for their networks. Apple has always been ahead of the smartphone trends, why lag behind on this one?

iCloud: iPhone 5 is expected to feature the new iCloud service in operating iTunes for wireless remote access of music from all computers and mobile devices. The iCloud will also store photos, apps, calendars and documents without storing them onto the phone's memory storage.

iOS 5: Apple's iOS 5.0, which is the newest of the OS versions, was announced on June 6 at the WWDC 2011 keynote address. The new iOS 5 is expected to come with 200 new features that will include Improved Notifications System, News Stand and iMessage. It will also feature new applications, such as the Reminders app and Newsstand, an application resembling Folders and iBooks.

NFC Payment: There have been reports since early this year that Apple is testing an iPhone that incorporates Near Field Communication technology. Users can simply pay for goods by waving their iPhone in front of a contactless payment scanner. Mobile-payment services using NFC will be a hot segment in the future. The technology could offer features that allow multiple mobile devices to sync for speedier information exchange and gaming.

World Phone with SIM-less Design: Making it a worldphone, the iPhone 5 is rumored to feature a new SIM-less design with two to three internal antennas for CDMA and GSM compatibility.