I haven't heard anything about a new stepping. As far as I have seen, D2 is the one and only stepping available. Batch number might make a difference though. My 2500K overclocks to 4.8GHz stable, and I'm happy with that. You have to get very lucky to get higher than that.
manuelars:
I answered your question in your own thread. Please don't ask the same question in other peoples' threads. It's bad manners.