Video explains the workings of the new 7-speed manual gearbox as well as the ratio gearing of the 7-speed PDK.
This brief video explains the gearboxes offered on the 2012 Porsche 911.
For the 7-speed manual Porsche offers a very sporty gears 1 through 6 while the 7th gear comes with a long ratio for improved fuel-economy. Performance is not sacrificed at all as the gear ratios up to the 6th are fairly short and top speed is, indeed, reached in 6th gear and not the top gear.
The video also touts the PDK 7-speed box which is geared much the same way, with the the first 6 gears made to deliver performance while the long 7th helps out with fuel-economy.
On the 2012 911, the gear lever is also closer to the driver, as the center console is elevated compared to the previous model, making for easier manual shifts.