i checked today since there was a update in network and physx, the jumping vehicles, and it seems that nothing changed or its worse.
here is tank vs truck: http://www.youtube.com/watch?v=WqqpXo-5zlI
here quad vs truck: http://www.youtube.com/watch?v=8Rjkt5TnPzs
watch the second one till end i am driving under a "bug-lifted" truck with
all in multiplayer / dedicated server.