Welcome aboard, citygirl. We did this trip two years ago, only from Montreal to Boston. Ports are the same, though. My review is located here: CruiseReviews - LP Maasdam CNE
and I am happy to answer any questions. We've done portions of this itinerary several times, although on different ships.
Maasdam has since undergone a major refurbishment that has expanded some public areas. I haven't seen these first-hand yet, but they have been implemented on several of HAL's sister ships and I've heard a lot of positive feedback.