Ethanol = biofuel
Many parts of this country have been using 10% ethanol fuel since the early 90's. It became pretty much the standard once MTBE was found to be entering ground water and was banned nationwide. You've probably been running it all along. We've been using it here in CT since the mid-90's.
Yes, ethanol can damage your fuel system as it's hygroscopic and absorbs water, much like brake fluid. It can cause rust and corrosion in the system if it sits for years at a time. It can also form a gel type substance which will block small passages and jets. This is especially problematic in power equipment that sits in your shed or garage. My best defense to this has been Startron fuel additive. If you drive your car on a regular basis, you have nothing to worry about.
Ethanol can attack older rubber components, such as fuel hoses and o-rings. If you have hoses that are over 20 years old, it would be wise to change them regardless of the fuel you're running. Modern fuel hose is compounded to be ethanol resistant, as are components in new carburetor kits and fuel pumps.
From the article I read, the administration is raising the total gallons that must be incorporated into the fuel supply, not the mandated percentages. This keeps the corn growers in the Midwest happy, as something around 40% of corn is used for ethanol production. The percentages are mandated to be displayed on the pump, so if you have a choice, use the E10.