It's pretty straightforward to get permanent residence (a 175 / 176 visa) if you're in IT. The process will take a year, cost two or three thousand quid, but is generally pretty straightforward.
If you can follow instructions then you don't necessarily need to hire an immigration agent either, which is another big saving. :)
From what I've heard, I'd agree with the characterisation that the east coast is suffering, whilst the resources sector is booming. In fact, a friend reckons the state of Victoria is already in a recession. The trouble is that most of the IT work is in Sydney and Melbourne.
At the current exchange rates, contract rates seem to be on a par with London (most are $600 to $900 per day, about £400 to £600), permanent salaries are a touch higher. Living costs are higher, and some things, such as cars, are eye-watering.
Housing is also really expensive. Melbourne is on a par with London, whereas Sydney is completely bonkers. Prices have started to slide, by around 5% in the last year. If this is the start of a bubble bursting, then the Australian economy could be in for a rough ride as a large proportion of the population has significant mortgage debt, or even loss-making investment properties.
I'm tempted to head over there later this year, though probably as a temporary (6 to 12 months) stint.