In the foreign release of this film the producers wanted all the singing in English, and all the dialog dubbed. There is one scene where Goldie Hawn is speaking while Alan Alda is singing live on the set. This segment of singing had to be re-dubbed into English by Vocal Contortionist Jeff Bergman - Segment Produced by Roy Yokelson.
In Venice when Woody Allen is singing "I'm Through With Love" the vaporetto boat in the background is going backwards, along with a smaller boat a little later.
In the x-ray room, the nurse calls for Katie to come and look at the engagement ring in Drew's stomach, but the nurse that arrives has "Judith" on her name badge.
DJ: [as a narrator]
And, of course, my stepbrother Scott, who's very smart, but currently on the outs with the family, because he's become a conservative Republican, which has caused my stepfather to have a stroke since we're all liberal Democrats.