Thanks for the additional replies.
Tom, if it is a privet and I've never seen it flower . . . is that because it's young still (about 3 - 4 years) or because it's a variety that doesn't flower?
Anyway, it's in the pot now, so I'm just going to see what happens for this year.
It's a fairly large pot with lots of room for new roots to develop, so maybe it won't slow down too much in any case, at least for awhile.