I've only done one transfer for a co-worker and the miles posted within 5 minutes. Haven't tried it myself as my points with both VX and AS are now all used up on future bookings.

Other people did have problems when the names didn't match exactly on both accounts. I also had a duplicate MileagePlan account set up by Alaska in the status transition and had to call to get the two accounts merged. You should call if they haven't posted as there is either a glitch or there is something wrong with your MileagePlan account.