You are credit tightening yourself. Others, as we have clearly seen, do not do so and are doing what is necessary (High DTI, High LTV, IO and Neg arms loans) to get into a home.
This may not compel you to buy, but for the ignorant masses that what X house and Y monthly payment (regardless of the terms from what we see in the bubble areas) they will still buy.
To FormerSanDiegan :
The number of speculators and second home buyers is significant, but is it enough to drive the market down or is it just as likely (if not more so) that we face a period of relative stagnation.