The market chaos has left no top investment bank standing. Of the Big Five, Lehman, Bear and Merrill are gone, while Morgan Stanley and Goldman are becoming commercial banks, which means they can no longer put up the house to borrow billions for high-stakes deals. They'll have to chop their leverage in half if they're going to meet current banking regulations.
The new power ranking, however, will look suspiciously like the old one—except for names like Barings (which bought parts of Lehman), Bank of America (which now owns Merrill Lynch) and JPMorgan (which gobbled up Bear). That is because even as the markets force them to wind down their riskiest deals, the firms will remain the top players to provide the corporate underwriting by which investment banking is rated. But the regulation push will likely prevent the new titans from raking in profits the way the old did.