My friend had the main Dominion game, and then splurged and picked up Dominion Seaside and Intrigue. Played one game with the Pirate Ship last night. I'm not entirely sure that I like that. It's a nifty idea, but they appear to be be overly game changing. It seems you either have to play to screw people over with them, build to have a specific counter to it, or reach some unspoken agreement that no one plays them. We had a four player game and only two of us buying them. I think we had 7-8 between the two of us. Pretty much the rest of the game was spent with me and him trying to get coin counters while the other two just sat and waited for the game to be over. The only counter really was Secret Chamber, so you could discard what you wanted to the top of the deck and guarantee no money would be flipped, but unless all three of the other players had secret chambers or no money on the flip, it was token city for the one who played PS.
It's also entirely possible we didn't have other cards out that really work well with/against it, so I'll reserve my deepest ire until after a few more games with them. That being said, some of the other cards looked really interesting. Can't wait to get more games in to see what the new cards are really like.