> How does Net Apps measure browser market share that they get such huge difference for IE, which they put at 54%, compared to StatCounter who puts it at around 30%? To me the StatCounter numbers seem more accurate.

Apples and oranges. Net Applications measures users, while StatCounter measures usage. It is entirely possible both are right, and the different numbers are both accurate about what they measure.

It is also possible one or both is wrong, possibly by a large amount - we don't have any good data against which to validate them (that data exists, but it isn't public - Google and Facebook know the truth).