I think in advance you can assume you are going to need a valid IELTS score, so if you don't have an IELTS (or equivalent) certificate you'd be well advised getting one. They are valid for an application for 2 years once obtained.
Also your work references and other supporting documentation you can start looking into.
However, the date that applications will re-open is as yet unannounced. Early 2013 is as specific as Minister Kenney has hitherto got.
Since the new EOI proposals are unlikely to be in place until late 2014/early 2015, next year's mainstream FSW will probably have a modest cap, maybe just 10,000 again or even less. It seems there will not be an in-demand list and that people will be eligible with 67 points and at least one year's experience with any 0, A or B trade.
This is all strong rumours but nothing is completely confirmed yet.