My wife and I retired almost three years ago. It has been wonderful, and the issue that my kids worried over (what will you do with all that time?) has not been an issue at all. So:

How do you spend your time? We bike, exercise, travel, and do "grandparenting" duty.
What might you do differently? Save earlier and retired earlier (waited until I was nearly 69)
Have any of your "goals or priorities" changed? We've put a greater emphasis on healthy diet and more regular exercising. Would like to do more bicycle touring while we can.
Has anyone felt the need to work "part time" aside from financial reasons? A passing thought from time to time, but hasn't been necessary yet.

How has it affected your interests like cycling---or other interests/hobbies you might have? Not a big change, just a little more time to pursue our interests. We did buy a tandem, so that was a fun change.
Who has traveled--and where---especially for cycling vacations? Several road trips in the US each year, Europe once and plans for more. Not as much cycle touring as we'd hoped. Have one planned for this summer and hopefully a bike tour in Europe next year.

Has anyone just got bored or tired of cycling because they have so much time to ride? How did you deal with it? Not bored, but often sidetracked by other activities. We've decided to move biking higher on our priorities.
Any words of wisdom or lessons learned from those that have more experience with this retirement thing? When our kids started moving out, and again when we started planning on retirement, Sharon and I sat down together and made lists of shared activities we were interested in pursuing. I think it is the smartest thing any couple can do when approaching a major life style change. Worked for us.