Thinking of extending my visit to Singapore to either Seoul or Hong Kong. Any suggestions?

Factors that would influence my decisions are:
- nightlife (gay or otherwise)
- ability to converse in english
- size of expat population
- local cuisine
- costs
- exotic cultural stuff

I've been to HK b4 on a one night stopover, but I didn't do much as I was so jetlagged.

Trip would take place June/July 2006, and the HK or Seoul part would be for 5 nights.

Comments would be much appreciated.