Is it right time to buy brokerages?

Today again negative subprime news are coming to market. Citigroup (C) predicted high losses due to credit market together with CEO resignation are dragging market to red. I'd like to focused on group of investment brokerages. This segment was hit heavily due to subprime lenders issues. Current P/E valuation of US brokerages is 9.5. Goldman Sachs (GS) has 9, Morgan Stanley (MS) 6.5, Merrill Lynch (MER) 12.3, Lehman Brothers (LEH) 7.8.
In my view Morgan Stanley stepped down the most from the record price and this company has still Q3 results announcement ahead. Of course P/E ratios don't tell us the shares are cheap now because all brokerages earnings are let's say disappointments and adjusting their P/E valuation. Do you think is it right time to buy brokerages? I still stay away and waiting..