What do you think was the overall message?

That women are big heartbreakers.

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"If you put your mind to it, you can accomplish anything." -George McFly

That you can do everything right for a woman and it still isn't enough?
That she will play around enough with your emotions and expectations that she will act interested in you again after a long separation, flirt, share a train ride home with you, and then invite you to a party that turns out to be her engagement party??? (And her explanation for it later: "I did it because I wanted to." W-T-F?!)

I'm still coming to terms with this, after watching it for the first time last night. It's a quality film, certainly, but the part where Summer invites Tom to her engagement party was thoughtlessly cruel on her part. That was the straw that broke the back.

Maybe the film's strength and weakness, is that it's actually too much like real life...

"Everyone else may be an a**hole, but I'm not!" - Harlan Ellison

I loved the film. I think its a very mature look at the concept of love which is more often than not a mismatch between the couple. I don't think it has a message, but it explores what love is. One thing is that both people do act mature in the film; though he has his heart broken, he doesn't stalk her or attack her. Neither are depicted as the bad person in the film. She is very upfront about her expectations and talks to him about it. Also she broke it off because of their fights; exactly how much they fought is not shown because its from his POV, but there are hints.

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RIGOLETTO: I'm denied that common human right, to weep.

I think that overall the film has a positive message. Tom spent over a year trying to get Summer and win her over, and while there were happy moments with her in his life it also caused him a lot of heartache and grief. Perhaps that might seem like a waste to some, but if Tom had never met Summer he would probably still be alone and writing greeting cards. She inspired him to become the architect that he always wanted to be, and in so doing he met Autumn who seems like a much better match than Summer was (at first glance, anyway).

It's like Summer said about being 10 minutes late to the coffee shop, or if she'd decided to go to the movies, her life would have been a lot different; if Tom had never experienced the pain and heartache that Summer caused him, he would never have met Autumn. Summer was not his soulmate, althought Tom wanted her to be, but Autumn may be.

The (500) Days of Summer attitude of “He wants you so bad” seems attractive to some women and men, especially younger ones, but I would encourage anyone who has a crush on my character to watch it again and examine how selfish he is. He develops a mildly delusional obsession over a girl onto whom he projects all these fantasies. He thinks she’ll give his life meaning because he doesn’t care about much else going on in his life. A lot of boys and girls think their lives will have meaning if they find a partner who wants nothing else in life but them. That’s not healthy. That’s falling in love with the idea of a person, not the actual person.
- Joseph Gordon-Levitt

i would say that's partly the message that might have been portrayed, personally i think it's as simple as sometimes relationships don't work for a reason and you may need to reflect on them and know what you or/and the other person did wrong and learn to move on and realise there's more to life, but then what do i know.

I don't know if I see the film as presenting a message but I think it really tries to capture the essence of memory and how subjective it is.

I recently wrote a review of (500) Days of Summer on my blog. If you're interested in more of my thoughts, you can check them out here: http://realworldromcom.blogspot.com/

I take it as a warning and cautionary tale for men-

When you meet an attractive female. who clearly, right upfront, states "she does not want a boyfriend or anything serious," just enjoy the FWB and NSA sex. In the mean time, find a nice girl who is the marrying/serious type. Once found, dump the bimbo for a real woman, someone who does not play head games and is into commitment.

Forget all the self-absorbed, ego-maniacal, head game playing, phony, pretentious, kuntz out there. There are still a few good woman out there. Don't waste your time on the bad ones.

Women will destroy you in the end.