The new version of Dynamics AX 2012 looks very nice, and it can be downloaded from Mircosoft partner source.
But one of the initial reactions to the released hyper-V, was that I experienced that the performance was poor. I especially saw that refreshing forms took several seconds. We quickly saw that it was not lack of hardware, because the hyper-v was allocated with 16 Gb ram, 4 CPU cores and a raid for disk.
But I found a solution that worked perfectly for me :
Then the AX 2012 RTM on hyper-V started to live up to its claim of 20 times increase in performance compared to AX 2009 on selected areas.