It really depends where you are, to.
In my part of Baltimore, Triumphs are by far the dominant brand, followed by old UJMs and Ducati.
In much of the rest of the city, it's Japanese sport bikes. Lots of Gixxers.
In the burbs, more cruisers. Harleys and their clones.
I was just in Portland Oregon. Old BMWs were the norm. Only saw a few Harleys, lots and lots of BMWs, GS100s seemed all the rage.