So the 5th placed team beat the 3rd placed team. Fantastic achievement by Australia for being genuine underdogs going into the series and then delivering a killer blow. However I wouldn't rank this win any ahead of Pakistan's 3-0 whitewash of Eng in UAE.
The clinical, almost effortless win by Aus shows how volatile the top tier is barring SA. The gap between the top 5 teams haven't been narrower ever. I am not sure that is a testament to "quality" of cricket being played but I prefer a bit of competition and mongrel.
As to England, I think its fair to assume that their purple patch is over. They had a chunk of players who concurrently were in their peaks (Anderson, Swann, KP, Bell, Prior) in terms of age and experience in the last two years, but now they all in all likelihood are past it. If the English mgmt is not careful, having all these chunk of players who are suddenly and collectively on the decline can have a multiplier effect on the team performance which can result in solid whippings like what is happening now.It happened to India when their core which brought them so much glory all descended into terminal decline together (Tendulkar, Sehwag, Laxman, & to some extent Dravid and Gambhir). Some of the current players need a kick up their backside, nothing more effective than having young pretenders gnawing at their neck for their position. Prior desperately needs competition, so does KP and Bell. Management needs to project Panesar as not just backup but a serious competitor for Swann's place and let him know that.
The positives from the series for Eng have been Carberry and Broad. Carberry needs a fair run in the team whereas Broad has been outstanding.