I don't buy the safety in case something goes wrong bit any more than I buy the interference bit that has been the usual answer to why you cant have your laptop on during these times.
They won't let you have your laptop, or tablet, or mp3 player, or ebook reader, some say because they want you to be able to pay attention incase something goes wrong. Load of crap if you ask me. If that were the case, how come I can sit down, buckle up, put in ear plugs, and fall asleep, all before we've left the gate, and no one says anything? Or why can I pull out a 2 pound hard back book the size of a shoebox (I exaggerate, but not by far), and no one says anything?
If its really for safety reasons in case something goes wrong (the pilot fails in his job of keeping the plain from hitting the ground), that hard back edition of Lord of the Rings/Harry Potter/Sword of Truth will do a lot more damage flying around the cockpit than my 6 ounce kindle.
I've always liked looking out the window on takeoff and landing, so I've never had a problem having my various tech turned off during this time, but the "it's only 15 minutes each way" argument irritates me. There have been numerous times that the plane I was on had to wait somewhere between leaving the gate and actually taking off, or between landing and reaching the gate, once for over an hour, but they still demand we keep all electronic devices off. 15 minutes I can handle, but being forced to stay seated for over an hour without at least having my kindle to read is all sorts of annoying.