They seem to have figured a lot out since then. The 3-rotor motors they currently use in Grand-Am/Rolex have pretty long intervals between rebuilds.
It's a shame to see them drop the rotary completely. The rx-8 never really lived up to the hype for me. There were always quips that direct injection would save the rotary while making more power and helping with emissions, but I guess it wasn't to be. Hell, they even made an all aluminum prototype 16x engine a few years back. Guess it didn't work as good as it looked.
I had always hoped that they could build an all aluminum 3 rotor sports car, but alas, I'll just have to save up tons of cash to do it to mine.