I read on pinside that someone received a Tron with a build date of 19 April 2012. So they have been running for a while it would seem. No Tron LE though just Pro's.
Yes, said it back on page two of this thread so emailing Stern to confirm was a bit redundant. They are also doing a short run of Avatar and Rolling Stones as well to fulfill a specific customer order (most likely Betson Amusements or one of the other 800 pound gorilla customers they have since I can't see any other demand for either of those titles otherwise.)
Crystal balling now, but I predict the price point gap between second hand Stern Pro and LE models to become even more pronounced (particularly Pro models falling)
I would wait on this one for a while (unless it is a must have).
Another outcome that Stern didn't anticipate with the tiered pricing model (or maybe they did?)
Edit:
There is another run of Tron Pro being done as we speak by Stern. Friend in the US just had his delivered yesterday - build date April 19th 2012.