the 2012 yamahas were just announced last week but won't be out til spring. No changes to the VX series except color choices.
Usually a good time to buy is in the dead of winter (and during boat show season) but this year, inventories are lower than normal this time of year due to the Tsumami stopping production for a while earlier this year--while you may get a few hundred more off waiting til winter, you may not find the exact ski you want--may not be as many leftover '11s by then compared to a "normal" year--the VX is the #1 selling ski in the world so it sells fairly fast. If it's a matching VX to the one you have, may want to go for it now--it's end of season so deals should be pretty good.
We bought ours (FXHOs) last August to make sure we got what we wanted rather than wait (and to get two that "matched"--my wife thinks that's neat

)--we got a pretty good deal and also got to ride them for a little while before winter.