That is but just one card. The whole 3XX line is pretty much the same exact cards from last generation. How much more performance does an extra 50MHz on core realistically give you in games? The OC headroom I fear will be close to nil. Factor on top of that the 290/290X were BOTH overheating beasts that needed to be tamed by AIB partners ASAP because reviews were bashing the crap out of AMD's reference boards. When the 390/390X come out, please compare the prices with current 290/290X and tell me if that is competition.
If the 390X is as fast or faster than 970 and cost slightly less or equal then how is there not competition. You are also assuming that they have not addressed the heat and power issues of the 290X. Given the capitalistic environment in which both companies exist AMD isn't going to create a package that won't sell. Also Maxwell doesn't offer any features that AMD can't offer with GCN.
So far with the leaks we have seen AMD has an answer to the entire Maxwell line up.