The first wave of 802.11ac is shipping now. It brings great benefits like 1.3Gbps from a single radio which is almost 3x the speed of a 450Mbps 802.11n radio. Wave 2 of 802.11ac is set to deliver Mu-MIMO, more spacial streams, wider channels, and generational inprovements like power consumption and signal processing etc. However, is wave 2 worth the wait? Some are saying that wave 2 is set to hit the market in about 18 months but with Quantenna recently accouncing their new wave-2 chipset, the QSR1000 family, we might be seeing wave 2 sooner than that.
Richard Watson with Meru takes a deep dive into wave 2 and MU-MIMO in the following blog post. Check it out and see if Multi-User MIMO is Nirvana .. or .. not?