Once Ivy Bridge launches, even LGA1155 platform will have more than sufficient bandwidth for videocards courtesy of PCIe 3.0 in Ivy Bridge CPU.
Secondly, Ivy Bridge should bring anywhere from 7-18% more performance per clock in applications as a result of architectural improvements and a much more aggressive Turbo Boost 2.0:
Thirdly, it will have even lower power consumption.
Fourthly, it will likely overclock higher than 4.9ghz you achieved on your 2700k, completely negating the purpose for an i7-3820.
In other words, in just a matter of months, Ivy Bridge will basically obsolete the entire LGA2011 platform, except for those who actually need 6 cores / 12 threaded CPU for web development, video encoding, encryption and rendering.
To me, the only reason an extremely expensive platform is justifiable (> $500 per CPU + $250 for mobo) is if that platform performs much faster in all situations, not just in 3-4 specific situations. A computer user can simply buy a $225-332 Ivy Bridge quad-core CPU and reallocate the savings from LGA2011 platform towards a faster GPU (or say a 2nd GPU) or a larger SSD, almost always making such a decision better than going with the overpriced LGA2011 platform.
Worst of all, Intel's "high-end" platform keeps launching after their mainstream platform. So it will take another 1-2 quarters before Intel releases Ivy Bridge-E. Intel should have just called LGA2011 a workstation/server platform and never called it their high-end platform. With the launch of Ivy Bridge, there will be nothing high-end about a $550 3930 CPU that will get whooped by a 5.2-5.3ghz quad core Ivy Bridge in almost all situations that apply to common users (office tasks, games, Photoshop, etc.).
And then the cycle will repeat again. Intel will launch IVB-E in Q3 2012, but then one might as well wait for LGA1150 and much faster Haswell. In my opinion, the strategy behind LGA2011 is completely inconsistent. At least LGA1366 launched a full year earlier, allowing early "high-end" adopters to claim exclusive performance over mainstream users.