I am through my first real 'season' of swimming, my longest swim was a tide assisted 10K in Germany; my toughest swim was the 5K at Coney Island, my coldest swim was in the fjords in Norway and a swim into the current of one of the feeding streams there.
I train for the exercise, for the joy of it, but mostly for the open water experience- no OW swim is ever the same. I am training for some longer OW swims next year (Chesapeake? if I can get a spot, maybe the swim from Fire Island back to shore), and long term I want to test if I can swim a real marathon eg MIMS...
My short term goal is to get faster in the water, it is very tough to swim in currents without a bit of speed...