TechRepublic.com reports: "802.11n is being touted as the networking standard that will unwire the network world. Most people are not convinced, yet curious to see how one defends such a claim. The 802.11n standard has two top-level mandates (unwiring the world not being one of them): Achieve higher data rates and retain backward compatibility with legacy 802.11a/b/g devices. The significance of requiring backward compatibility shouldn’t be taken lightly since it complicates the development process exponentially. Yet the 802.11n group has come up with a soon-to-be-ratified standard that meets both objectives."
This is probably the best article that I have read to date on the 802.11n standard. It appears to be most complex and featured pack of all the 802.11 specifications released so far.