Actually it won't be any leaner but it will be down on power. Ethanol contains less BTU's per unit volume than does gasoline. Expect a drop in power and an increase in fuel consumption.
At the 10% level, it won't do any damage to the fuel system. Beware some of the Northern states such as MN where they are talking about going to 20%.
Ethanol isn't too bad in terms of corrosion but it is both hydrophyllic and hygroscopic so it makes a bad bet for long term storage in that the water from the air can and will corrode some of the components.
I am from Brazil and here we use 25% , not a problem for the FI but the carbs clog if the bike see some storage time The loss of power and fuel consuption is the bad effects , i feel sorry for you guys , welcome to my world