MIMO alliances are shifting as Qualcomm brings its good self and patents to TGn Sync: EE Times reports that Qualcomm has dropped its own plan, a kind of third alternative, and will join up with TGn Sync to support 20 companies including Cisco, Intel, and Atheros. The issue of RAND is not mentioned in the article: that's reasonable and non-discriminatory terms for licensing intellectual property.
The TGn Sync Web site says their proposal offers up to 315 Mbps of raw bandwidth with two antennas. Throughput would likely be at least 200 Mbps based on other details they provide. TGn Sync wants the option for 10, 20, and 40 MHz channels and two to four antennas. (The article cites different numbers, for some reason.) Lower speeds would be possible with fewer antennas and less spectrum allowing MIMO to be fully deployed in newer devices that don't have the power or necessity for full TGn Sync speeds. They even expect 600 Mbps flavors in what they describe as "larger" devices.
The folks at WWiSE, which includes Broadcom and Texas Instruments, are concerned about international use of 802.11n, and propose four antennas and the current 20 MHz bands. This provides speeds up to a raw rate of 135 Mbps. The article doesn't mention WWiSE is interested in options that would allow 2, 3, or 4 antennas and 40 MHz bands. WWiSE states in their primary navigation that they're offering RAND. The technical details at WWiSE show their position clearly: they believe they're offering better spectral efficiency.