Not as concurred as the Rialto bridge, the Ponte dell Accademia is a perfect spot for lovers in search of a romantic spot at sunset. (click on picture for high res)
PS: We have returned from our five days stay in Venice. Absolutely wonderful since we could witness the Acqua Alta (high waters) as well as sunny days.
Leica M9 with 60mm Hexanon at F1.2, 1/60, ISO640