Same here. I was in tank city last night (selflessly sacrificing my tank rank to clear the campers off the spawn point, but we won't go into that...) and also noticed that there is a lag between my becoming 'visible' at the spawn point and the nme tanks becoming visible to me. This, of course, caused me to die more times than necessary to clear the spawn point. I would up, jump to the gun, and wait for the tank I KNEW was at my 2 to become visible--I had just seen him in that spot 15 seconds ago. I also noticed that my shells were sometimes going RIGHT THROUGH the other tank early in the session, exploding on the building behind him. This is not good when you're doing 'quick draw' snapshots. Usually, the first hit wins. At 100 yds, it's hard to miss.
FYI, I have high speed internet and 60-70 ms pings...