As the world continues to sift through American subprime rubble, several additional shoes are ready to drop: Alt-A mortgages, Prime mortgages, land and construction loans, and...commercial real estate loans. Thus far, commercial real estate loans have been (relatively speaking) safe. That happy era may be coming to an end.

Today's NYT describes a large apartment complex in New York that is about to default on a $225 million mortgage payment. This would be New York's largest default so far, and as consumer balance sheets continue to deteriorate, there will likely be more to come.

How much of this commercial property loan exposure is out there? The NYT estimates more than $100 billion, which would be a tiny slice of the $500 billion Alt-A and $1 trillion subprime markets. But whatever the exact size, it's still real money, and the big Wall Street banks are carrying around a boatload of it:

Lehman Brothers: $40 billion

Deutsche Bank: $25.1 billion

Morgan Stanley: $22.1 billion

Citigroup: $19.1 billion

Writedowns have trickled in from banks such as Morgan Stanley and Wachovia. But the collapse in value of this particular asset class has likely only just begun.

See Also:

That Awesome Warren Buffett CNBC Interview

NAR Spinsters: Housing Still A Mess, But "Buyers Are Responding"

Citi Buys Bob Toll's "Pent-Up Demand For Housing" Story (TOL) (TOL)