It's a great way for them to get you on their email list. Use your disposable email address if you don't want to receive the spam.
As for the content, you can bet they'll want to get you to sign up for some of their annuity products, or insurance policies. Keep in mind that the current state of Soc Security can't stand. Of the proposed solutions, the 'increase the retirement age' is the standard solution, but is receiving push-back from the baby boomers who are themselves retiring now. The 'remove the SS-tax-cap' solution is starting to gain traction, but there seems to be no political will in congress to make any changes to Soc Security - the "third rail" of politics.
Couldn't hurt, I suppose. If you have the free time, and go in with your defenses up.