Pretty much like any big city and not only in Asia - KL (Kuala Lumpur) is a busy and noisy place filled with lots of smells, tastes and endless streams of people and vehicles.
We stayed next to Chinatown and Little India, and apparently our street served also as a dropping point for all sorts of immigrants, so it was never ever even close to being quiet. Every shop in this area makes it its primary duty to play music louder than the neighboring shop, and every sales person in the market will assume you desperately need a fake Gucci, Prada or Louis Vuitton watch, bag or a T-shirt. (On the other hand you can shop in Chinatown Petaling market till you die and what you buy will actually be really cool stuff, a cool T-shirt will cost you anywhere between $50 and $5 depending on your bargaining skills)
Behind the food courts and eateries in chinatown there is a wet market - a hidden labirynth of inside lanes filled with everything you eat sold in a raw format - veggies, chickens (some alive, some with guts out), pig heads and legs hanging, all sorts of fish, eggs, rice and condiments - all laid out in front of you as it is. It's a scene that is quite different from what we're used to see in supermarkets. After about 3pm the stalls are already almost empty, and the place turns into a swirling rat kingdom. (yes, rats are everywhere in KL)
The architecture is really mixed, among huge glass buildings with business offices, casinos and shopping malls you'll find 2 storey chinese houses, Hindu temples and colonial time European looking buildings. Petrona towers is of course the highlight, making them literally always visible lighthouse wherever you go in KL.
Another huge attraction (at least for me) in KL was Central market - a shopping mall entirely dedicated to selling traditional arts and crafts - man, this place can satisfy even most sophisticated arts and crafts lovers, interior and fashion designers, extraordinary lifestyle lovers and generally people who love surrounding themselves with nice things. Purses and bags, carved wooden art, dining accessories, coconut and sandalwood decor, batik textiles, hand made jewellery, organic oils and creams, table games, souvenirs, hand painted shoes, custom designed furniture and much much more.
Overall however it's not that interesting city to be in, but lucky for us we got some friends there and our hostel was one of the most fun places we ever stayed at, their staff really made us feel at home (Moon Lodge owned by Moon, an extremely kind Indian guy who is Christian and doesn't speak Hindu, somehow it seemed like a crazy combination of features) We had many parties and get together evenings at the roof top of the hostel, and we also got to do a BBQ one Sunday, Moon and Asai (a super friendly always smiling Chinese guy working at the hostel) helped us with the grill and fire.
Generally people in KL are very friendly, same as in Singapore it's a mix of Malays, Chinese and Indians living there. Each bring their culture, language and food. Malay food in KL is really spicy, their curries and sauces are competing even with Indian ones. I found though my favorite drink in KL - teh tarik (teh - tea, tarik - to pull) which is tea made with condensed milk and pulled from one can to another several times. Most of the times they add ice in it and carry it around in a baggy with a straw (love this baggy!!!)
Also, there is something special about Malays - they don't know. Nothing in particular, generally - they don't know. Try asking people on the street about anything - directions, names, metro stops, is sky blue, and you'll get a very Russel Peters style wiggling hand gesture accompanied by "I dunno".
During our stay in KL we got to witness pro democracy riots, nothing too violent, but still a bit scary especially when you are located in the epicentre. About 200 protestors got arrested, no serious injuries, just lots and lots of tear gas in the eyes and mouth. It was over the same day and the city continued its regular life right away.
We also got to go to a local culture and arts festival Urbanscapers 2011. It was an open air event combining live music, flea market, theatre, games, food, exhibitions - really fun times especially after getting to see performance of local beatboxers and hip hop stars. One amazing difference between an event like this in KL and in Europe is that in KL all the young rockers, punks, hipsters, rappers, artists participating in the event are sober - sober youth at an open air festival deserves a "wow" from Europeans. Not that there is no beer, there are outdoor beer stalls, but somehow it doesn't get even close to what happens in Europe.