Blu Ray v2. No, it's not called HD-DVD, but is actually codenamed 'Sapphire'. Unfortunately, they were only given the most brief of mentions at Sony's CES Press Conference, and we're hoping to find out more juicy details soon.
All we do know is that the two current models are reported to have some pretty fancy-sounding features, that will hopefully include a better loading time. According to Engadget:
"Named Sapphire 1 and 2, we don't know what makes them different from each other, but the only features listed are 1080p24 output, and support for x.v.Color, Sony's term for the xvYCC expanded color space."
So I'll just go with them on that one. It will be interesting to see what new features they both incorporate, because without some slightly more impressive stats, I see no reason to particularly favour these beasts yet. Of course, one year on from now, at the beginning of 2008, we'll all be using BLU-HD-RAY-DVDs and be running them on Tri-boot systems with Mac Os X, Windows Vista, and whatever spiffy open source OS Linux can throw at us by then.