I've noticed a contradiction in the wording. The tour says this:
Accepting doesn't mean it's the best answer, it just means that it worked for the person who asked.
But the hover text for accepted answers (i.e. hover on the green tick graphic) says this:
The question owner accepted this as the best answer < time >.
So is the accepted answer the "best answer" or isn't it? These two descriptions really ought to be consistent.