I think Warney's retirement will have several effects. Some of them more immediately evident than others...
It'll take the Australian public some time to to come to tearms with the fact that most spinners get tonked around more often than SK Warne did. Sure, Warney had his bad days, but they were comparatively few in terms of tweakers.
The other international teams will perceive a deficiency in the Australian bowling attack (especially in absence of Warne & McGrath), which could open up great opportunities for Australia's less known bowlers.
Remember, Stuey MacGill has out-struck Warne every (yes - EVERY) time they've played a Test match together.
The Australian bowlers may find that they need to work harder to ensure that they continue to wrap-up tail enders as efficiently as they have in the past.
Because we won't have Warne to slow the run rate in the middle overs, the bunnies may find themselves with more freedom to play their shots (on the back of larger totals).
Keep an eye out for a marked change in Australia's field placements in the second half of the innings.
There'll be more pressure on Australia's batsmen, especially in the middle overs, as the chances of Australia rolling teams for under 200 have considerably decreased.
I'm sure there will be many other ramifications that will become clearer over the next year.
But this is all just speculation really... I guess only time will tell!