That's true an over years read many people that dropped their canon rebel and they were surprised it didn't shatter into a million pieces and often still worked as good as before. Some brought it to service centers just to be sure.

I never dropped my camera though, but i do run into things a lot, doors, doorposts, fences and most of all tiny people.

Though with a bit typical lens 70-200 or some people often bring, i doubt the difference in weight of the body plastic vs metal is really noticeable. (plastic rebel XTi 556 grams vs 668 grams metal nikon d80)