Low interest rates make consumer loans more accessible. It's much easier to service a 5% loan than a 10% loan.
Here's the National Federation of Independent Business survey about what are the primary concerns of business. Interest rates/financing is last ... pretty much at an all time low.
http://www.nfib.com/surveys/small-business-economic-trends/
I'm pretty sure that if I dug up the Federal Reserve report it'd also show that banks have excess reserve (i.e. money that they'd love to lend at a reasonable interest rate rather than earning 0%).