Update. I ended up buying the 3Gb/s version anyway since, as it turned out, the 3Gb/s version comes with a necessary (for me) HBA SATA controller card included. The 6Gb/s version however, does not.

Since it seems it's still not possible to connect drives larger than 2TB directly to any Intel southbridge controller (in my case, the most recent one: ICH-10R) and use it in ACHI mode, I decided to go with the 3Gb/s model.

The order has been placed. Is it normal to be excited about the upcoming arrival of a new harddrive?