Australia - Christmas and New Years suggestion

[Xtrema]

Thinking of spending some downtime in Australia this winter. Any suggestion of what to do?

Also, any good cell/data plan while out there?

[Feruk]

MUST do's:
1) The Whitsundays: Google it, absolutely beautiful islands. You can fly into Prosperpine (or something like that) and take a sailing trip from one of several beaches for a few days. Just amazing.
2) Fraser Island: Island where the beach is the road. I booked a 3 day tour with a company that takes like 14 people in one big car. Camp overnight. Lots of fun, highly recommend.
There's a company that does combined Whitsundays/Fraser Island tours which are pretty cool.

Should do's:
Byron Bay - this is great for partying and surfing
Noosa - another cool town on the Sunshine Coast but less cool than Byron
See an Aussie Rules or tennis match in Melbourne

Could do's:
The big cities. I went to Sydney/Melbourne/Brisbane. Meh. Very much like Canadian cities.