DS definitely doesn't get 2 hours of screen time a day. He would be lucky if he gets 15 mins a day if I am home.
We have lots and lots of books, and he loves to read. We also spend at least 1/2 hour every night reading to him.
I remember being bored when I was a kid, and I used to hate it. So I feel bad that DS is just laying around doing nothing.
Fifteen minutes a day? In this case, I'd say an increase is definitely a no-harm, no-foul proposition. These kids are going to grow up in an increasingly digitized world, so the more comfortable they are in it, the better.
We have no electronics policy in my home. DD has independent access to a number of electronic devices, and unless there's something else she needs to be doing at the moment, we generally don't interfere. But as much as she enjoys these things, she doesn't spend two hours on any of them in a day combined (unless it's a family camp out night, which always includes a movie). There are always other things she'd like to do, too.
She's got a Nintendo DS she keeps in the car for long trips, but lately, all she wants to do there is read.