I think it's far less sue-happy than people think it is - but when you do hear of a ridiculous lawsuit, it will certainly be off-the-wall and for an exorbitant amount of money. Sadly we have a flawed legal system (in oh so many ways) and you will find abusers of the system - and that holds true for any kind of system that can be abused - when they can make a personal gain without much risk.
For example, the reason we have a stupid warning on coffee cups about the contents being hot, is because someone decided to sue for getting burned by coffee. This may not have escalated as quickly elsewhere in the world - not because someone wouldn't try it, but perhaps the legal system would have laughed at them instead of allowed for a case to happen. It's not the US culture at blame, and the lack of such people elsewhere in the world who would attempt to make such a lawsuit happen - it's the system that people can easily abuse - and miraculously are able to get away with it.
edit: I stand corrected by rfurmani and v0cab below - I actually did read up more about the hot coffee case in the past - and the details completely slipped my mind while posting this. It is not a good example and doesn't really fit the point I was trying to make.