Comments from a home network veteran
Good article. For the record, HomePNA is a 2 wire technology -- the same PHY operates over both coax and phone wires (most North American use like AT&T's U-verse IPTV are over coax. Phone is used in the rest of the world).
This type of wired home networking is widely used for commercial triple play IPTV and VoIP so Service provider support is important. G.hn is heavily supported by telcos but IEEE P1901 isn't. There is a lot of information comparing G.hn with IEEE P1901 and home networking in general on the HomePNA blog. http://homepnablog.typepad.com/
Also, I was working at one of the major 802.11 companies during the PHY wars. There were three 801.11 PHY technologies and direct-sequence spread spectrum won for technical reasons - frequency hoppers couldn't deliver the higher data rates in the same bandwidth. The market window opened and volume drove the price down. G.hn has put technology first in its standard development.