Other than the normal windows stuff - we aren't doing much, We have a group policy that runs after login to backup files (which doesn't work when only wireless)
When only wired, things are fine, when wireless and wired are both on, depending on priority, it can be slow.
Now to add more oddness into this - I don't see this much in my office (I'm with the controller, but I also don't log in on wireless much) We do see it when we have visitors from other offices, and we have one office in CA that seems to get this issue alot.
They have AP105's installed connecting back to us over a MPLS circuit.
Lirria