Indeed, Hong Kong is still an attractive destination for everyone in Asia. nowadays, the most numerous (by far) visitors come from mainland CHina. Depending ion their status, they either run to buy perfumes, baby milk powder, medicine, etc... as Hong Kong products are the originals whereas counterfeited products about in mainland CHina. Or they form lines in front of Vuitton, Chanel, Hermes, Gucci, Fendi, etc....
Hongkongers recognize the income from these mainlanders, but at the same time are often pissed off by these wealthy uneducated peasants.
There are still many visitors from SIngapore too. To go into comparisons, I'd say Singapore is greener, with parks, tree lined avenues etc. but at the same time more boring, as the government still has strong moral positions. You feel the city density more in Hong Kong than in Singapore, but everyone recognizes Hong Kong is a better place to have fun in restaurants, bars, dices, etc.... Along with this goes more prostitution, drugs, etc.