Ethanol can cause all kinds of heck, even in newer products. For example, just last year, I had to replace a fuel hose on my lawn mower because it was dry, brittle, and cracked. It may have been a coincidence, but it just so happened that Arizona started putting Ethanol in their summer gas as well as their winter gas that same year. If it was coincidence, it was amazingly timly!

Some of the issues I know about with Ethanol are (and I learn more all the time):
1) Some fiberglass reson is readily disolved by Ethanol. The first separator system we sold was to a guy who had an engine out because of this very reason. Also, some boats are affected by this.
2) Some rubber will either swell or get dry and brittle in the presence of ethanol. I talked to one guy who was using ethanol fuel because his engine was rated for it, but came to his hangar one morning to no fuel in the tanks and fumes in the hangar...ethanol had ruined his fuel likes like my lawn mower...he felt lucky he didn't have a huge explosion when he opened the hangar door. BTW that rubber is found in carbs, fuel lines, and some fuel tanks/linings.
3) Some tank sealers that some people use in their aircraft are disolved by ethanol.
4) Alcohol is a cleaning agent, and can if you have any corrosion in your fuel system, it can make it flake off and clog carb jets and what not.
5) Alcohol attracts water, and can therefore trap it against metal surfaces, causing them to corrode. This exacerbates the problems related to #4.
There are more, but these are the "big hitters"

As far as the argument that racers have been using ethanol exclusively for a long time. Yes, they have, but they also rebuild their engines a LOT more frequently!

As a general rule, engines do not have issues with alcohol...it is usually the fuel delivery system that is the problem. So even for older cars, yes, they will make it across country fine, but they will likely need a carb rebuild more frequently. And if you want to continue to use original parts, you will continue to rebuild the carb. The antique auto industry continually deals with things like this. Some of them have even resorted to putting an inline fuel filter where there was none, just to help keep the affects of ethanol at bay.

Anyway...I am sure all of this stuff can be found in other places...this is just kind of a summary...enjoy!