Codenamed N13 Series, the chips are ten in number and are divided into three categories, according to the target consumer segment.
The N13E are the Enthusiast-grade models and will arrive next year, in January (N13E-GS1) and April or May (N13E-GTX), though the samples will ship earlier (early November and early 2012, respectively). They have 2 GB of GDDR5 VRAM backing them and 256-bit memory interfaces. The mainstream and low-end GPUs will arrive earlier, during this year's December in fact (2011), with the mobile parts set to appear fastest. This means that their first samples will be sent out during early October.
Their memory will be of 1 GB or 2 GB DDR3/GDDR5 and the bandwidth will be of 64 bits or 128 bits, depending on model.
All in all, the codenames are similar, in pattern, to the N12 that spawned the 500 series of adapters, though changes may still happen by the time anything is made official.
The info and specs should be taken with a grain of salt as it's nothing more then a spreadsheet filled out by someone.