The year 2008 saw just 25 bank closures in US, and it was dwarfed by the 140 bank closures in the year 2009. And the US FED had already warned around October 2009 that the financial condition of over 415 US banks were very weak and good number of these banks were ripe for collapse in 2010.
The same seems to be slowly coming true, with 26 banks getting closed down in the US in just the first nine weeks. The US has been running at high speed till 2007 when housing loans commercial property loans were doled out liberally to almost every citizen. But with the economy turning bad since the beginning of 2008, people slowly started seeing their property prices not appreciating as expected. Also by the middle of 2008 many of the people saw their property prices go down substantially. That created a panic selling by good number of people which resulted in massive increase in supplies while the demand started vanishing.
Banks added fuel to the fire by cutting down sharply on new property loans thus reducing the demand further. The economic downturn later on pushed down millions of people out of their jobs and businesses. All these people defaulted on their housing / property repayments.
And that is now reflected as massive unbearable bad debts in most of the bank balance sheets. The bridge is only crossed half way through as of now, say experts. So the worst may come and hit the entire globe anytime in the future.