I went for my honeymoon earlier this month and I loved it!
The canals don't stink unless your very very enclosed, the beggars are pretty much gone apart from the odd one or 2 about the place, be prepared to punch a few rose sellers if you go out anywhere at night, it took me screaming in their face to piss off!
The thing I really wanted to go on but didn't as we went very last minute was the Venice by night walking tour. Let me know what's it like if you go on it!
Practically, get a pass 3day pass for the vaparetto water bus tings, they go all over the show. Use the airport shuttle to come in from the airport, was €15 I think.
Go on a gondola, at night it's awesome and a lot quieter
f**k museums, the whole place is living history and just wandering round getting lost will keep you busy and learning all sorts, and that fascinates me more than a museum of mainly religious tings.
We stayed at Hotel Savoia & Jolanda which was right next to the bridge of sighs, we had a suite overlooking the lagoon an a balcony which was awesome.
EVERYTHING is expensive, no exceptions. If you're walking about an fancy a drink, go in a shop or buy one off a seller, neh the cafes, Feckers will take €4 for water or upto €7 for a coke!
Oh and atleast €100 for half an hour on a gondala!
Enjoy it mate!