Cover or not ?

[stevierst]

Give it a quick wipe down, and chuck the cover on. It'll do the bike no harm covering it wet unless you have a sealed environment for it, which I presume you don't.
Back when I was covering 500 mile weekends commuting in the winter, I used to get home, hose the bike down with cold water, a quick wipe with a towel, WD40 all the engine/downpipes/frame, and chuck the cover on it. I did 30,000 miles on that bike in about 18 months, and it looked like new when I sold it!!! I wouldn't worry yourself too much about stowing it wet, it's a lump of metal at the end of the day, it's not going to dissolve over a week or two!!!