The extended delay in approving the standard, which was first developed in 2002, stemmed primarily from competing "pre-N" technology from Atheros and Broadcom and their resistance to finding a common ground for the standard. While this was eventually settled, the competition led to the IEEE agreeing to certify so-called Draft 2.0 802.11n devices in March 2007 with the promise that these would eventually be upgradable to the final standard. The group went so far as to promise no major changes in 802.11n or its certification process.
The standard is already found in most modern computers and a small number of handheld devices and theoretically connects at 300Mbps, or about six times the peak speed of the more ubiquitous 802.11g format. Some of this speed comes from Multiple In, Multiple Out (MIMO) antenna arrays that piece together an incoming signal as it's bounced around an environment, improving not only the maximum speed but also the usable range.