I'm coming up on 58 and can testify that when I turned 50 was when my tolerance for a lot of things changed. On the other hand, my general acceptance of a lot of other things got better. I guess it's a mixed blessing. Either way, 50 was a changing point in so many ways.
Dan, 60 will be a huge change for me because it will be when I get to retire and take up residence in sunny Florida.