Muse, I would say just the opposite. For gaming it would be about a draw, maybe the Z560s would beat Klipsch even. The Z560s have more power in the sub, which may create a better gaming experience; though it is a little too much for DVDs. Both generate plenty of sound from the satellites.
The bass on the Z560s is very muddy. It may be loud but its not clear. For that reason alone, the Klipsch are much better for music. The Klipsch satellites seem to have a lower range helping to pick up the "upper" low frequencies. Thats just going by ear though, as Logitech refuses to release detailed specs on the Z560s.
The Z560s do win hands down on price, and at $130 they are probably the ideal choice for most people. Its just not true to say they are the better speakers, just a better value for most people.