I am no expert on processors, but can say that the AMD Turion 64 X2 is a brand new chip from AMD.
It is reviewed in the Aug 2006 issue of PC Pro magazine which has just come out.
Although generally favorable it does say that "The Turion 64 X2 is not something that will set the world on fire. There is little chance of it overhauling Intel Core Duo".
Of the 3 on your list the 64 Bit AMD Turion is the oldest I think, so it is between the other two.
Overall, unless you plan to do any power computing I think all three will be plenty powerful enough, so maybe look for which laptop offers the best price and specification.