Initially expected to be ready by the end of this year, the PCI-Express 3.0 specification has been officially delayed and will not see the light of day until Q2 2010. According to PCI-SIG (PCI Special Interest Group), the body in charge of the development and management of the PCI bus, although PCIe 3.0 is almost finished, the workload needed to ensure backwards compatibility and electrical requirements has proven to be significantly larger than anticipated, thus leading to the mentioned delay.
If the PCIe 3.0 specs will be done in Q2 2010 and won't suffer a new delay then the first products to support it, like graphics cards and motherboards, will arrive as soon as Q2 2011. PCI-Express 3.0 will feature a 8GT/s bit rate (up from 5GT/s with PCIe 2.0) as well as a number of optimizations for enhanced signaling and data integrity, including transmitter and receiver equalization, PLL improvements, clock data recovery, and channel enhancements for currently supported topologies.