Fishing Master sequel, Mezase!! Tsuri Master Sekai ni Challenge!, is coming out this winter in Q1 2009 under the title Fishing Master World Tour. The controls have been made a bit more representative than in the previous title (there's less holding of buttons and more just motion), and the backdrops now include exotic locations around the world. Like one might see on a tour of the world. It's also got boss battles and leaderboards. I played it briefly at E3 and found it pretty easy to operate (but really hard to successfully entice a fish in).
The other nautical game takes place underwater, and in much smaller bodies of water. The WiiWare aquarium thing Blue Oasis will be released at an undetermined time under the title My Aquarium. The official North American website launched this week.
[Update: the release date for Fishing Master was apparently in error.]