On the 319/320/321's I know they actually have 2 strobe lights on each wing, one goes off then the next one right after that, IM
pretty sure that the Boeing's just have the one strobe. The DC/MD 10's and MD
11 have one strobe on the front and one on the rear of the wing.
In response to your post, yes I would say that is a pretty good way to tell them apart in during the night. Also the landing lights between the Boeing's and buses are different.