The AMD killer is the complete lack of mobile chips. Since mobile is 75% of the market now and Nvidia owns 90% of it, that gives AMD a 7.5% total share. Add that to the 50% of desktop and they have a 20% total share.
If AMD can take back a decent chunk of mobile, it'll give them a huge boost. Especially since the mobile variants go for 400-600% more than the desktop version. Well for Nvidia anyway, AMD may have to stick with 200-300%.
I own cards from both companies (latest was a GTX970 before the truth came out), but Nvidia has screwed with me to many times now...I can't buy/recommend them anymore. Not unless they stop their crap for a few generations to show they've really turned around.