I just finished up a trip to Singapore and I think that if you have the time, you should totally spend more than the three days many say to stay. Here is my blog and photos on it

I recently finished a week long trip to Singapore to catch up with an old friend. When I told people that I was going there for a week, several people gave me a grimmaced look, and told me that I shouldn't stay there for longer than three days, and that I would be bored. I can safely tell you that I could have easily spent more than the week that I did, and I could happily do several weeks as a traveling nomad (especially if I was working).