The league just emailed me the exact Saints pre-season schedule. Here's a look at the dates and times.
Thursday, August 12, 2010 - Saints @ Patriots - 6:30pm CT
Saturday, August 21, 2010 - Texans @ Saints - 7pm CT
Friday, August 27, 2010 - Chargers @ Saints - 7pm CT (CBS)
Thursday, September 2, 2010 - Saints @ Titans - 7pm CT