I've heard that there won't be any more significant changes until July 2012 apart from the introduction of the new Points Test at some stage.
On 1st July 2012, DIAC will move to the Expressions of Interest system that you have described. Apparently they intend to collect EoIs between July 2012 and January 2013 and then they will invite people to apply for visas from Jan 2013 onwards.
The process of obtaining a skilled GSM visa will then become much quicker because the staff won't have huge backlogs of applications to deal with.
Also, the new system will prevent any more fiascos of the type that led to DIAC's ill-considered decision to use S39 of the Migration Act to Cap & Terminate all the GSM applications that were made prior to 1st September 2007 but had not been processed by May 2010. The people whose applications have been arbitrarily kicked out have been offered a full refund of the fees they paid to DIAC. However DIAC have refused to pay any interest on the money. They have also refused to give any refunds for the fees wasted on skills assessments, medicals, migration agents etc. DIAC say that they can't refund money that was not paid to themselves.
This purported use of S39 is now the subject of litigation. A well known solicitor called Chris Levingston has instituted formal legal proceedings on behalf of at least one of the affected applicants. Apparently it is not allowed to be a Class action with lots of different Plaintiffs but if CL's client wins, it will open the floodgates to claims for compo from all of the others. The litigation will also be very expensive because there will be appeals and counter appeals.
The Aussie Government's international reputation for fair dinkum has (deservedly, in my view) taken a heck of a hammering over the s39 thing.
In May 2010, the then Minister for Immi suddenly introduced the Cap & Kill Bill 2010, trying to grab absolutely draconian powers for himself. That idea was kicked out by the Senate.
I think that the EoI idea is much simpler and more elegant. I think it will work well.