I don't think anyone should see the fall in real estate as a symptom of deflation. Is is quite simply a market correction due to prices reaching levels that could not be sustained by peoples' earnings. Once average house prices get back back in line with the historical norms of, say, 4 times average earnings, they will start rising again (may over shoot on the downside of course), especially not the US Treasury is standing behind all the mortages.

As for stocks falling, we know why the bank stocks are collapsing (they are insolvent). The commodities are going down because the powers that be have orchastrated a take down forcing the hedge funds, who are leveraged, to get liquid fast. This is not deflation, it is an attempt to manage inflationary expectations, i.e. to make us think we are in for deflation and hence allow them to continue to inflate.

The Fed and the other central banks are replacing all the lost capital with fresh money. The money supply goes on increasing as it has done since 1971. There will be no deflation, don't be sucked in by this. The Fed stands ready to create money "without limit" remember. They don't even have to print it these days, just tap a few keys on a PC.