boston boutique hotels
I almost forgot - depending on when you plan to travel, there's another boutique hotel scheduled to open in June/July of this year on 90 Tremont Street "Nine Zero". (FWIW, a third is scheduled to open in the Fall in Kenmore Square - The Hotel Commonwealth).
The only one I'm familiar with is XV Beacon. I've only been to their restaurant (though not recently) and haven't seen the rooms. The lobby is striking, and I've always had great service there. One of the nice touches is the complimentary in-town chauffered-driven Mercedes (which they kindly offered once in lieu of calling a taxi after dinner). Link and information below: