I posted about a month ago asking for recommendations in York, and got many responses. Thanks to all who replied! As you'll see, your suggestions provided most of our eating experiences...below are a few highlights; the full writeup of the trip is on my blog, http://eatatjules.blogspot.com.
The best lobster we had was at Fox's Seafood by the Nubble Lighthouse, a friendly place with very fresh lobster and a nice, casual atmosphere. We went at night, but the view during the day must be great.
Great lobster was also to be had at Barnicle Billy's etc., the sit-down version of the very popular Barnicle Billy's more casual lobster shack in Ogunquit. The two places are next to each other.
The ambiance winner had to be Chauncey Creek lobster pier, where we watched fisherman bring in their day's catch while we ate.
We also tried Street & Co. in Portland, which I found to be good but a little split-personality. The starters on the menu were Mediterranean-influenced and in some cases a bit experimental, but the main courses were pretty basic and in my mind, somewhat disappointing after the promise of the first courses. On the plus side, the seafood (scallops in my case) were fresh and cooked well.