Got my copy yesterday and i was blown away.

Presentation:
the overall presentation of the city and the flair of the 50s is just stunning, eventhough the city seems not as living as liberty city in GTA IV but facing the fact that life during that time wasn't as hectic as in the time GTA plays it feels pretty adequat.
Gameplay:
for now it feels a bit repetitive, it always follows the same structure:
briefing
investigating the crime scene
interview suspects
drive to place a,b,c snoop around and ask people
nail the suspect with evidence
but it works like a charme, due to the fact, that all persons and places are individual it doesn't feel like doing the same over and over
Graphics and Audio:
it isn't a red dead redemtion even though it comes pretty close, there are some slowdowns and popups here and there, but that's marginal it looks good but not stunning. so much for the world, the real eyecandy are the faces and their animation, never seen something good as this before. remember the adds for the ps2 with emotion engine, now la noire shows what an emotion engine is!
audio is nice, here again its the characters and their voices which are nothing but the best i've ever noticed.
Story:
didn't find a string yet, every case is its own story, but i guess they all stick togehter from clues you find on every crime scene but i don't know yet.
Controlls:
basic GTA/RDR like control-sceme which works, i haven't had a moment with a feeling the guy on the screen doesn't do what i want.

Conclusion:
If you thought it would ne GTA in the 50s you'll be disappointed cause there is not a chance for a maniac killing spree through the city, also there's little action in it, it is more of a read the persons find the clues and such game. Open World Point and Click Adventure would be accurate. The game lives through its persons which are nothing than the best to be in a videogame.
i've played it for 6 hours straight yesterday and it felt like five minutes, and that's nothing but a good feeling.
score: 95%