[anotheryou]

I'm no expert and might be horrible wrong on the math, but I imagine it like this:

2 bit => 2 ^ 2 => 1 of 4 possible state

2 qbit => 4 of 4 possible states. That's 4 times the information (although extraction of the information is limited)

With bigger numbers:

10bit => 1 of 1024 possible states

10qbit => 1024 of 1024 possible states (1024 times as much)