If you wait for the next thing you will NEVER have anything.
If you have the money now, get your system now because even with SB coming out it's going to be a VERY long time before X58-based systems are underpowered.
If you want to wait a few more months to see comparative benchmarks then it's your choice, but bear in mind then that the socket 2011 top-end Sandy Bridge stuff is due only a few months after that.
Also, AMD Bulldozer is due around this time as well, and that's supposed to be excellent as well.
See what I mean about waiting?
See your point in the never getting anything with waiting so I will just buy the 950