Stand alone IBs might be......a thing for the past. IBs usually have a leverage of 30 or more, a few folds of that of a conventional commercial bank. This level of leverage will be hard to survive the current market conditions.
MS has a leverage of 20 at this moment, which is probably the lowest for the firm for the past few years. However, they still need to hold merger talks with commercial banks like Wachovia, which has a lower leverage (10) and a much better buffered balance sheet.
Another option that MS is exploring right now is to seek more equity injection from CIC, potentially to a maximum level allowed under a minority holding - 49.9%.
RBS has also been highlighted recently as a potentially risky UK bank. After the ABN acquisition, RBS' balance sheet is still considerably weak. It is also very much exposed to the UK mortgage market, which might suffer from a spill-over if the credit crunch unfold further in the US.
Congrats in nailing the interviews and good luck to you.