You know, I really enjoy this thread. But what I enjoy most, is to see what transition someone will make from one picture to the other. Like the time someone made the transition from crosswalk to zebra (stripes) which was awesome. To push toward this goal, I would add a new rule to photo tennis:
(3) Do not use the same transition subject as the poster before you.
Now, we've just seen 6 bikes in a row. You guys might as well start a new thread called My Bike Shot. To me, it just feels like the ball didn't cross the net.
I know I just contributed one shot to this entire thread (not much of a photographer myself) and I'm in no position to set rules but I enjoy this thread and hope to keep enjoying it in the future. You guys are photographers - be creative!