I just got my macbook back from the shop and the "t","g", and "b" keys weren't working earlier. They seem to be working now. Among the things I had them look at was a trackpad that wasn't working properly. If they continue to act up is there anything I can do? If this thing needs a new keyboard or topend is that something I could replace on my own or do I need to send it back to the shop or would a replacement keyboard for a desktop be a cheaper alternative?