I saw it tonight and I was very disappointed. SPOILERS AHEAD!
The first 40 - 50 minutes was good, perhaps even very good (it had a similar feel and authenticity to 'Good Will Hunting'), but after that it just lost the plot both literally and metaphorically. For me there is nothing worse than viewing a movie which begins to take itself seriously and then turns about and disengages from it's 'modus operandi' to impress certain Hollywood production sticklers and comply with a target market audience.
Moreover it didn't represent bi - polar disorder accurately nor any major mental illness for that matter. Actions have consequences, the movie seemed to skip that major truth about life which detracted from its overall authenticity. The movie began feeling 'soul driven' and genuine, but gradually, and at times 'jaw droppingly' that feeling dissipated and by the end it was a gross misrepresentation of what it set out to be.

It was too predictable. It was frequently corny and in particular the house betting fiasco scene which was entirely off kilter with the rest of the film and so was the night of the dance (dirty dancing in reverse role scenario and rehash of 'strictly ballroom' for the egocentrics) and the penultimate scene rung too much of 'When Harry met Sally' and most other cliched Hollywood romantic comedy endings.

From about 50 minutes onwards very little of the script was original nor was it even a smidgeon thought provoking. A lot of the writing involved character's telling their theories on popular books, superstition about football teams, the necessity to own an ipod and which music is best. One thing it did highlight well is how materialistic and basically obsessed our society is with consumerism and modern fads, but I am unsure if that was the intention of the director. Robert De Niro and Jacky Weaver were miscast and totally unbelievable in their respective roles. Particularly how Jacky Weaver was nominated is one of the greatest mysteries of oscar acting nomination history.
I did however like the music and think the soundtrack was excellent. Other than that I am giving it a 5/10.

I cannot remember seeing such a poor Oscar nominated film especially one which started off with such promise only to turn into a Hollywood satire of itself by the end. Go see something highly original and genuine throughout like 'The Master', which unfortunately hasn't been nominated as best picture probably because it's way ahead of it's time (my review http://www.imdb.com/title/tt1560747/reviews-208) or 'Life of Pi' (my review at http://www.imdb.com/title/tt0454876/reviews-335)