Aug. 11-14: vs. Minnesota Vikings
Aug. 18-21: at St. Louis Rams
Aug. 25-28: vs. Chicago Bears
Sept. 1-2: at New Orleans Saints
As I believe I've mentioned before, my primary interest in any schedule announcement is making travel plans. Travel for preseason games seems like a bit much even for me, though I did go to Green Bay in 2007 and there's a chance I'll attend the St. Louis game this year.
Actual game dates and times will be announced later this month. None of the games is currently scheduled to be nationally broadcast; all will be shown live in local markets and will be shown on NFL Network at some point (though probably not live). The only preseason opponent the Titans are slated to face in the regular season is the Saints.
If there is a disappointment when it comes to a preseason schedule for a preseason that may well not be played, it's that the Vikings, Rams, and Bears are all fairly pure 4-3 teams, and the Saints are primarily a 4-3 team. With close to half the league, including now the Texans, playing a 3-4, it'd be nice to have a preseason game against one of them, but no such luck.