The No Brainer Annuity or 4% from Investments Which Is Better.

Annuity Option: 
From http://www.immediateannuities.com/  if you want a cash stream of $3000/month you would need to $677,000 to purchase that security.    Risk is low assuming inflation does not go crazy and the company selling the annuity does not go bankrupt.   Additionally, you would have to read the fine print...

Investment Option:
A better alternative might be to get 7% investment return on your money in a 3% inflationary environment, you would get $2256.67 per month on a $677,000 dollar investment.    The main risk here is that you would have to earn 4% better than the inflation rate and your investments may have larger risks.   A huge benefit of this option is your principal is never effected.    That offers you an emergency fund or travel fund.  

Most of The Current Generation Are in Charge of Their Own Retirements

For better or worse, most of us are in charge of our own retirements.   To make things worse if you are planning on retiring after the baby boomers retire (born in 1946-64) you will likely experience government interference with your social security benefits coupled with medicare cost increases.   As government tends to only face problems that are eminent or immediate, expect some drastic and desparate solutions to your social security and medicare that will be taylored to the publics well being and not necessarily to you.    So, you have to start planning today for your retirement tomorrow!