DISCLAIMER: I haven't read the book that this film is based on and I certainly don't have the privilege to interview the film makers to understand what they intended to portray through the story.
However, I believe the filmmakers not only intended to tell a story but wanted the audience to be in the driver's seat post intermission.
This movie is all about the characters and a very unusual narrative arc, rarely seen in Bollywood. I can remember just one in recent times (Kaho Naa Pyaar Hai), but this story pays off much better for the almost three hours journey we take.
The story starts off with two friends trying to find their friend from when they were all studying Engineering together. We get introduced to Aamir's character, Rancho; but through the eyes of the friends', Farhan (Madhavan's character), Raju (Sharman's character). The narrative arc of the film gives the audience a chance to see what the friends find in Rancho, and how they all bond. We are welcomed with open arms right from the start.
Both these characters are loveable and will remind us (sometimes painfully) about our past or a close friend of ours from back in the days.
But wait! Just as we get to the intermission, we see an unusual twist in the story that throws the characters in the film completely into a topsy-turvy world and because we were on the ride with them, we're confused just as much as them.
Here is where the cleverness of the filmmakers gets very evident.
Post-intermission, the film makers wants us to "rediscover" Rancho, but for ourselves and now Farhan and Raju are with us.
We're also joined by Pia (Kareena's character).
The film works perfectly because the Rancho we discover towards the end is someone we can relate to and to a large extent, we wished we could be if given a second chance.
Don't get me wrong, there are some highly "filmy" moments and the love angle between Rancho and Pia seems almost a tangent to the main plot, but somehow I felt like forgiving these small shortcomings because the story tied up nicely in the end.
TECHNICAL ASPECTS:
Art/Production Design - Even though the story is set in contemporary times, a lot of effort has been put into the minutest detail. For Ex.: Notice the torn banian on "millimeter", the hostel servant during his introduction sequence. I didn't notice anything out-of-place or any character (even the extras) unnecessary.
Cinematography - The framing and camera movements give you enough time to take in all the information at a very sub-conscious level. The bright lighting and colours are appropriate to the upbeat mood of the film.
Music - The melody is deceptively catchy. I caught myself humming to "Behti Hawa Sa Tha Woh" on my way back home, when I expected to be humming to "All Izz Well". I didn't like the high pitch background score in the beginning sequence of the film, but that could just be my personal taste.
Editing - I believed I couldn't enjoy long shots anymore because I had developed a shorter attention span watching MTV, I was wrong! Watch this movie slowly suck you into it's world without you even realizing it. None of the transitions (cut/dissolve) seem out of place.
Sound - A lot of importance has been given to diagetic (sound within the cinema's world) sound. You can even hear Pia's earrings and bangles clanging with each other when she's riding on a scooter in the climax sequence. Excellent work!!!