Just Like Heaven is a very good movie, except for the contrived ending. I don't like Reese Witherspoon very much, and I was a bit pissed off on seeing that she was the lead actress (I knew practically nothing about the movie except its title when I walked into the theatre). The hospital scene at the beginning didn't do much to change my opinion either.
However, things improve once she makes her appearance as a 'spirit', and the scenes involving her and Mark Ruffalo really sparkle.
Goof (sorta): How is Elizabeth able to physically control David in the bar when it has been shown earlier that she has no ability to interact with solid objects?
Goof (real): When Elizabeth tries to get David to sleep with the hot neighbour, you can see the microphone at the top of the frame.