As another reviewer before me, I also can't believe how badly people are writing about this film here. I adore Francois Ozon and I've seen all his feature-length films. This one seems quite different from the others (except, maybe, Sous le sable) and it's as low-key as Ozon could ever get, but it is still an excellently scripted and played film that makes one think.
I didn't consider the backwards structure to be gimmicky at all, it rather helped the viewer to better make out flaws early in the relationship. There is betrayal in each one of the episodes, starting with the last (chronologically the first) one. The film shows us that even little egoisms and uncharitable behavior can lead to grave consequences - in this case, to divorce. The woman, Marion, seems to be easily led anywhere, not having enough standing of her own, while the man, Gilles, seems to be egoistic, cowardly and sometimes just simply sex-crazed.
I think the structure rather helps us to understand the characters better, since we have already seen the consequences of their actions and attitudes. I didn't consider the large gaps between (and also in) the episodes to be a problem - they only acknowledge that the whole story can never be told because it is made up by every single moment between their first meeting and the last time they see each other. These episodes can only indicate what went wrong, they cannot explain - that would be too simplistic.
The actors were excellent, especially Valeria Bruni-Tedeschi. The way the looks of the main characters changed during the film (becoming more and more youthful and fresh as the story goes backwards), was also excellently done.
The parallel love stories (between Gilles's brother and his young lover, and between Marion's parents) shed some more light on the relationship between Marion and Gilles - also on what might have gone wrong.
This film should probably be required viewing for every couple wanting to get married... :-) Not in order to deter them, but rather to make them aware of the pitfalls of relationships and married life.
