Is it an age that you have to reach where it is socially accepted to 'retire' (*retire=quit your primary career and volunteer, invent, work for a cause, or relax on the beach)
Do you have an exit strategy? Are you going to work until you are 80?
Retirement Age? For Many, It'll Be 80 - SmartMoney.com Do I 'have' to work so Social Security is around for others?
Just like the government is cutting expenses, could you cut enough to be able to retire early? Would you be able to handle the 'unknown' expenses?
The big question is what kind of retirement do you plan, what will prices do, and how long will you need to survive in your home vs a nursing home...
(Edit: Why do I ask this... I have turned into a workaholic, relationships and friendships are only on-line, family is out of state, and my lifestyle inexpensive right now.)