Yes preferably you do need Sata 3 / 6Gbps for an SSD to actually value from the insane cash you pay for it. Unfortunately there are no boards that I have seen with more than 4 Sata 3 / 6Gbps ports.
Altough I dont see why you need so many SSD.
The Z68 chipset will support Ivy-Bridge, the next generation Intel CPUs. It has also quite a few bug fixes that were present in P67.
You can achieve better OC's and the PCI-e 3.0 boards are a nice way to future proof.
I have not heard of any issues with duel GPU setups on Z68 board. It should actually run abit better on a Z68 as it usually allows for more available PCI-e ports through third party controller add-ons.