There's been a lot of speculation but they (Alinghi) have not been out in anything but light wind yet.
BMWO on the other hand has been out in 12-14 knots and it has been reported that they saw to high 30s or low 40s.
If ether team goes with a full wing rig then you can expect a farther increasing in speed due to reduced aerodynamic drag.
There has been some wild speculation that we will see in excess of 50 knots. That would be fun to watch but I have my doubts.