My view is the $400K median is the absolute peak for Brisbane. People in Brisbane earn around $50K to $60K (household income) so despite the lack of supply or otherwise they simply won't be able to get the cash. Especially with the availablity of credit tightening. I actually predict a "lack of credit" induced price drop - to $350K median (or less) by mid 2008.
Feel free to save this post and laugh at me mid next year but I'm pretty confident.
The only thing that might keep it up there (post $400K) over the medium term would be government intereference in some way (higher first home buyer grants, tax relief for owner occupiers, allowing shared equity schemes or some other stupid policy like that).
I wont laugh at ya mate!! not in my nature
no seriously...I can't comment well on brisbane wide, but what i do know well (inner north and north west) is many of the buyers in these brackets aren't relying THAT much on finance that a credit squeeze will hurt them - most have money to burn or are borrowing small portions of the total cost.
where it will hurt is the first timers and lower incomes - how that affects things in general - God only knows...my bet is it will still keep rising based on what i am seeing on the ground every day.
cheers
UC