Taking into account what Dexter111 said just above me hyah; we can only hope that:GeneralTwinkle said:Valve has said before, in the case of bankruptcy, they will sever the steam client from your games. Unlike diablo III, almost all on steam don't 100% need steam to work, it's just you have to use it anyway. So there's no worry about losing all your games.
1 - they'll still have the resources available to do so upon bankruptcy
2 - that they'll actually do it, it's promising a lot, not to mention the third party issues already brought up; that and there's no clause so far stating that they'd do so.
It's an entirely goodwill idea, admittedly (as mentioned previously in this thread) the results could only be seen in a sink-or-swim situation, but it seems unlikely that such proposed contingency plans will become legally binding without a change in the law.
Then again, it'd be in their interest, removing the client rather than having to issue refunds (although neither are legally binding, just saying if they became so) would probably be preferable.