The few I caught over the winter were between 2.5 and 3 mph, which is a little more than I would consider traditional. Of course, those were on crankbaits, which run different than bucktails.
Probably has as much to do with what speed the lure had its best action at as what speed the fish are used to. If a striper wants a lure, he can easily get it at over 7 mph (since the salt water ones will at times hit lures trolled for bluefish and spanish).