Continuing to break up the team sports theme - not that I don't like those photos, guys - I finally got a chance to put your racing/panning tips into action. Not that the panning was too hard; speeds are pretty low in Auto-X and with the 50mm you're not super tight. I also put the focus on the * button and used the AI Servo, both of which worked extremely well. The 50mm did fine tracking on pans, but wasn't quite fast enough if a car was coming straight towards me. Overall, though, it yielded probably 98% usable results and maybe 60% or so very sharp. Taking my mistakes into account with the ability of this lens, I'm extremely pleased.
Here are a couple I picked from a lot of good ones. First, a Lotus Exige on full slicks. It was easily the fastest car at the event (among many very good cars). Second, Mustangs don't usually do so well in Auto-X, but this guy was doing quite well. Third, the driver of this S2000 on slicks was very fun to watch, pushing hard every lap, as you can see (that's a right hand turn!). The last one is a chicane at the end of a 60mph straight - he didn't get it slowed down enough, and the driver's face right b/f taking out the cones was priceless.