The IRS has published some useful data based on calculations from the dismal science's cousin, actuarial statistics. This data was compiled into a spreadsheet by the website
retireearlyhomepage.com. I placed their spreadsheet into a Googledoc spreadsheet
here. It's interesting that life expectancy seems to increase when the person in question has a spouse. For Kari and I, our table is as follows:

So each of us has a 50-50 chance of living for another 45.11 years. As a couple, the last survivor of the two of us has a 50-50 chance of living another 51 years.