I just got a mail from CW telling me that the v3 *WILL* have XTC in the next update. CW are waiting for emagic and steinberg (to pablofasan: not sonar) to fix their apps. Do don't worry, XTC mode will be included in the mac version too!
Logic has since 4.7.3 (released about a week ago) fixes for the problems with DSP such as Pulsar XTC and TC Powercore so there should'nt be a problem there.