The main difference between storage on land and storage on the water is one of worry. On land, once she was buttoned up, I maybe drove by the yard once or twice during the winter - trusting on the marina folks to call if something needed attention.
In the water, I'm more worried. My understanding is there are daily dock checks, but I doubt that anyone is going onboard and with her setting in the water, well, things could go south in a big way. So I drove to Rock Hall on Saturday morning and walked out on the docks. I found Seas The Day floating in her berth as expected on this beautiful day.
Once aboard, I check the electric to ensure it's on and charging (it was), and then opened the bilge to double check that the water was still pink from the antifreeze (it WASN'T - sorry, no photo). I turned on the bilge pump and turned to see foam coming out where the outlet hose had slipped off the black check valve. It was an easy enough repair (pull the two parts together and turn a screw to tighten the clamp). I switched on the pump circuit to empty the bilge and then went outside and used the manual pump.
While it was pumping I checked the weather. Of course we were expecting freezing temperatures - expecting 17 F in a day or so. For that reason, I decided it was worth a trip to West Marine to pick up a couple of gallons of antifreeze which were dumped in the bilge and pumped through both pumps.
So yes... some additional worry. Hopefully this gets paid off with the ability to cast off the docklines and go sailing earliest when the season starts up.