They said at the london fanfest the DX11 client is finished coding wise, it just needs optimising and they are working with AMD and Nvidia to make sure it plays nicely on both, they are hoping by end of the year to give an update regarding this area of progress. The 64 bit client, no news on that, but people want more visual upgrades, Im one of those considering I have the hardware to leverage it, game does perform well to begin with, so more visual options imo is the better start, what the game needs more over 64 bit is leverage 4 or more cores fully, multi core cpus are coming down in price, this will give people the biggest performance boost imo.