According to the Intel website the maximum speed is 2.9 GHz. So, the question is what is this Maximum speed as listed. Is it supposed to show you the maximum speed that the CPU is capable of or does it simply display the maximum speed that the processor has reached while Task Manager is running.
I suspect the latter, but we won't know for sure unless someone does some more investigating/testing.
I guess that it could also mean that Microsoft has limited the Max Turbo Speed of the processor to keep the heat down. This would be a bit of a bummer if true.