Yes, it has been confirmed that there will be a 3.0 H6 version of the Legacy available in June, but I hadn't heard that they would sell one with STi 6MT.
Word is that the NA base model Legacy will appear in dealerships in mid-May, and that the turbo GT will show the 1st of June.  It is expected that a fully-loaded GT will MSRP at about $28-29k.