The final spec isn't due to be done until 2009, which means we won't see implementations until 2010 at the earliest - giving PCI-E 2.0 a lifespan of about three years, about the same that the first generation will be seeing.
News from the group is this - the bus will handle eight gigatransfers per second, a phenomenal number. A spokesman for the group said that "The data shows that 8GT/s can be manufactured in mainstream silicon process technology, and can be deployed with existing low-cost materials and infrastructure, while maintaining full mechanical compatibility and with negligible impact to the PCIe protocol stack," meaning that by the time it comes to making this stuff, it will be doable.
Through a change to the way data is encoded and passed across the bus, PCI-E 3.0 will immediately knock 20 per cent of the transfer overhead off, creating an effective doubling of the current data rate.
We suspect that GeForce 12-series on PCI-E 3 will be a pretty nifty setup. ยต