I have noticed mine with a bit of a shimmy. Only seemed to start after I got the bike back from it's 2 year service a couple of weeks ago (big bore kit fitted at the same time).
Mine will move backward/forwards around 4 or 5 km/h (eg. when trying to sit on 80, it will swing constantly 78 - 82 ish). I have not mentioned it to the dealer yet, but will if I remember when next in there.