I've scored the $29 deal for return weekend in SYD from AVV.
Now how could any serious Frequent Flyer pass up the opportunity to add another airport to their list? :wink: 
I live about 15-20mins from Tullamarine, and about 40mins from Avalon.  When travelling for work I get a taxi or park in short term -hence would not consider AVV for work travel.
When on personal travel it is the long term car park, and the last two times I've used the long term, I've haven't found my usual spot (near the front corner) and have  drive around looking for a car park down the back, and waited for a shuttle bus (up to 15mins!).  Realistically you have to allow 20mins to be "safe" with that whole process, so if AVV have their sh#t together with parking, the 20 mins extra driving is neither here nor there for me.  The lack of a QC & FF points is though!
You've also got to consider the 200,000+ people who live in Geelong & the Bellarine Peninsula (as well as a substantial population in Werribee - who Jetstar are probably targetting), and the proximity to the Great Ocean Road, and I can see this airport working.