The latest rumor, this time from Bloomberg, confirms earlier rumors from other sources. Earlier rumors said that Apple's Pegatron and Foxconn manufacturers had begun building iPad 3s for a March launch, and that an LTE version would be coming this year.
The newest report sticks with the March launch date, and also claims Apple will launch an LTE version as well. The earlier LTE report, though, estimated a launch date of mid-year for the LTE iPad 3. That actually makes more sense, as second-generation --- and thus more real-estate and battery friendly LTE chipsets are not expected until Q2 2012. Apple is very focused on battery life, and despite the iPad's much-larger-than-a-smartphone battery, it's hard to believe they would sacrifice battery life on the new device.
Of course, that late a launch would break the iPad's annual refresh cycle, but since Apple showed with the iPhone 4S that going off-schedule, or rather, the off-the-schedule-Apple-has-kept-thus-far won't hurt sales.
The tablet will also use a quad-core chip, two of Bloomberg's sources said. The first Android tablet with a quad-core chip, the Transformer Prime with the NVIDIA Tegra 3 SoC (system-on-a-chip) launched late last year, but the iPad's success, and Android tablets' lack, has shown that specs are not exactly a sales point with many consumers.
The report also stated that the iPad 3 will carry a high-definition screen. While not specifying the resolution, it's already been rumored that Apple will double the current iPad 2 resolution with a 2,048 x 1,536 screen on the new iPad 3.
Earlier rumors also said the iPad 3 would be visually nearly indistinguishable from the iPad 2, although it be thicker by about 1mm.