Hi, I bought the MBA in november 2010, but it is only the last week that the heat has been excessive. The usage of the machine have been the same all along, so why all of a sudden does the overheating happen? And do you guys trust the smcFanControl? And the Mackeeper? What should I do, try to turn it on to get a new one? What is the reason for the overheating (all of a sudden)? Thanks!