Well, manual doesn't let you do stuff with your other hand.
Ummm have you ever used a manual? You only need to touch the shifter when you need to shift other then that your free to do what ever you want. I drink, change CDs, shave, read a book, do my laundry etc without any problems.
BTW another vote for manual. The main reason I bought my Xterra was because it was one of the few SUVs with a manual.