I'm surprised that this has been getting little, if any, coverage in the mainstream media. The ABC has had some stories about this, but I haven't seen much elsewhere.
The story behind the protests is long and complex and most likely will not resolve quickly unless there is an overwhelming use of force: Tiananmen Square 1989 style.
The 'TL;DR' version is that during negotiations for the return of Hong Kong to China, Beijing promised a high degree of autonomy for 50 years. This is the One Country, Two Systems model that was agreed upon between the UK and China in 1984. In 1993, the lead diplomat in these negotiations on the Chinese side, Lu Ping, described the level of autonomy as "How Hong Kong develops its democracy in the future is completely within the sphere of the autonomy of Hong Kong. The central government will not interfere."
The central government did not keep its promise, and has been interfering with Hong Kong's internal affairs incessantly for years, stymieing the development of democracy in the territory. The final straw that set off the protests is the promise of universal suffrage for Hong Kongers in 2017, however, they would only be able to vote for candidates approved by the central government. The equivalent of "you can have the car in any colour, as long as it's black".
Reddit has an up to date feed of information here, which might be interesting:
[live] Occupy Central Civil Disobedience Movement
There have been rallies in support of Occupy Central overseas. There was a small one in Melbourne this evening.