I fly a lot, about 120,000 miles a year right now. Many of those miles are on Virgin, which has Gogo In-flight Internet access and two 120 volt power outlets for every 3 seats in coach. This means I can do about 5 hours of work on a laptop on a cross country flight. When Gogo was free last holiday season (sponsored by Google for about 6 weeks), everyone was using the Internet on the flight and access slowed down significantly. There was heavy competition for power–the planes have a lot of juice, but not enough for 120 laptops. However, when it costs money, only those who really need or want to use the Internet are using it. Competition for power goes down, and the Internet speed is quite reasonable. For $10 or so, it’s worth it to me on longer flights.
If there’s anything that should be free, it’s checked bags. With the bags now costing money, people are bringing more bags into the cabin and running out of overhead space can cause delays. I was on a flight last Thursday where a woman had been forced to check her bag because the plane was out of room. Before we took off, she ran to the front (I was in 2F) and told the flight attendants her medicine was in the bag. We were delayed 20 minutes while the ground crew searched for her bag.