I think they should, but I don't know if they will.
If you want to play Pirate101 on Mac your probably going to just have to use a program like CrossOver or Boot Camp for awhile.
Hopefully we'll see KingsIsle make Pirate101 for the Mac too!
If they're close to have Wizard for Mac, then they'll probably make Pirate101 compatible at the same time. After all, it is a new game... much easier to add Mac support when making the game rather than later on.
If it is going to take that long to release Wizard101 to release for Mac (4 years) then I am sure it will take Pirate101 just about the same amount of time, either KI will not try to release it for mac or they will release it in 2 years at the minimum. I could be terribly wrong though, we will just have to see