Elite Bastards posted a preview on the ASUS P5Q Pro motherboard based on the Intel P45 chipset

One area where P45 does get a boost is in PCI Express support, with PCI Express 2.0 functionality added to the mix to double the available bandwidth per lane for compliant devices. Also added is the ability to run two PCI Express for graphics slots with eight lanes of bandwidth available to each, or as a single 16-lane slot if you aren't running a CrossFire multi-GPU configuration. For anyone looking to run a two GPU CrossFire setup on a budget, this is great news and a definite plus over the P35 chipset this architecture replaces, which had a rather hap-hazard approach to multi-GPU operation at best.

Another change that packages itself alongside the P45 chipset launch is the introduction of the ICH10 southbridge. Again, this is more about evolution that revolution, adding a couple of Serial ATA ports (for a total of six against four in ICH9), while ICH10R (with RAID support) sees no real changes at all, supporting the same AHCI and Matrix RAID technology we're already used to.

Intel P45 chipset - ASUS P5Q Pro motherboard preview