So far only Sandy Bridge-E and Xeon CPUs use socket 2011.
Sandy Bridge-E CPUs have six cores, but there aren't any games that takes advantage of six cores. Sure you can play games with it, but the 5th & 6th cores will not be used. Also, there are not many games that can use 4 cores, so the 4th core is likely to be idle was well.
Xeon CPUs are not ideal for playing games and they are expensive as well.
Intel will probably release the Ivy Bridge-E at the end of 2012 or beginning of 2013, but that has not been confirmed.
Haswell is Intel's next generation CPU architecture and that will be released probably in mid-2013; it will use socket 1150 and I really doubt the high end models will use socket 2011.
Basically sockets 1155 and 2011 will be outdated when Haswell is released. If you want to spend extra money going with socket 2011, then go ahead. Just realize that most of the time when you play games, you will only be using 50% of your cores. But at least you can brag about having a powerful six core CPU.