Don't know any friends of friends of anybody at VWGA, so this is all idle speculation. But it is based on what it takes to Federalize a car for US sale -
Powertrain (Emissions - EPA)
The 265 HP TFSI with 6sp DSG and haldex (not the current gen Haldex in the Golf R however) has already been federalized for US sale in the 2009 & up TT-S. It is likely the same specification powertrain in a Golf would pass emissions requirements with little or no changes. What has not been federalized at this point is a 6-speed manual configuration, this would require additional testing and cost on VWGAs part (perhaps this can be split with Audi of America if they plan on offering a 6 speed manual TT-S).
Safety Testing (Crash tests - NHTSA)
If both the 2 door and 4 door configurations are to be sold in the US, they will both have to be crash tested. Since the drivetrain, bumpers and other pieces are different than a Mk VI GTI for example, all of the possible configurations will have to be tested individually. Other safety considerations include dash structure, seats, seat belts, airbags etc. The Mk V and Mk VI are supposed to be world cars so few if any tweaks may be needed.
Now all of these costs to federalize a collection of Golf Rs for sale have to be spread across the X units to be sold. If we are only talking about 5-8000 units, this could get expensive for 4 main configurations (2dr DSG and manual, 4dr DSG and manual). The bean counters in Falls Church will have to crunch the numbers and figure out what makes sense.
As for useless predictions - IF we get the Golf R at all, I predict there is a 100% chance a DSG 2Dr will be in the mix. A significantly less chance (~50%) a 2Dr Manual will be offered as well. 4Dr DSG along with 2Dr about 75% chance, 4 Dr Manual alongside the 2Dr Manual probably less than 50%.
I'm in for a 2Dr DSG if they come, as soon as they are announced I have a check ready to go for deposit (and my email to customer relations from 9/17 says that). Otherwise I will hang on to my DSG Mk V GTI since the Mk VI offers virtually no improvement over that (I've already got an RNS-510 etc.)