I took my wheels to the LBS today, for this very reason--only I haven't touched the wheels. Ever. 1,000miles/1 year, and they have this clicky feel to them. But the guy there indicated that the only way to not have that clicking feel was to buy better wheels, like racing wheels. That it's just the way these hubs are.

Is he nuts? I think they are simply too tight, but if they are, they were 1,000 miles ago.