I couldn't stop wondering...
Why did they stalk him at the post office, why didn't they write first to get a reply?
Why did nobody else reply to the ad?
Why did she not ask him what happened the first time he went back in time?
Why was he able to call her, I don't recall them trading numbers when they first met?
Why did he need to steal all that equipment if he had done it once already?
Why did they need weapons?
Why did he say at the end 'I've changed the mission, we're going back for you'? I thought it had been agreed that they were going back to a date he had in mind which would also be convenient for her plans, although what plans are those exactly...how is she going to stop her mother from dying? Wasn't it cancer?
edit - I've since become aware that this had actually ran in a newspaper somewhere and the makers of the movie decided to use it verbatim in the film.
The movie was likeable and the characters were amusing enough, but there were too many spots where I realised that gaps in the plot were being papered over with jaunty music and montages.
I thought the most interesting aspect was the subplot involving her boss who has been given the chance to go back in time as it were and re-evaluate his choices in life.