I really enjoyed this movie. It was made by the same folks who made Summer Wars, so if you liked that movie then you'll enjoy this one too. And if you don't like that movie then wtf is wrong with you? ;)
Spoiler, talking about the ending:
From what I understand, the most traditional interpretation of the ending is that Makoto will "be with Chiaki" by making sure that he'll be able to see the painting in the future, by restoring it and ensuring that it is safe.
Of course, then there's also the horrifically dark interpretation that Chiaki is really a time-traveling con artist who tricks young girls (Makoto, previously her aunt) into becoming art restorers.
Here's a link for that read.
Anyway, what did you think, particularly of the ending?