I got the new 2011 MBA and was just wondering if you can keep it permanently plugged in on the battery charger? How many days can you do that for? It's going to be my primary computer and I will only take it out occassionally maybe once every two weeks. I planned to have it plugged into the charger the whole time without turning it off (but I notice it goes to sleep on its own if I am away for awhile). Is this okay to do? Are there any ill effects on the computer or battery? Thanks!