Looks like I have a new twist on this issue. I have a 2011 SHO with no apparent leaks but I get damp spots on the trunk mat and condensation on the rear window (when the weather is cooler, obviously). This only happens when there is a lot of rain. The car sits slightly nose down (maybe 2-3 degrees down angle) in the driveway. There are no apparent leaks around the trunk, meaning no water traces anywhere on the trunk seals.) And there is no evidence of water coming up from the seals to below. And I haven't found any evidence of leakage from the rear sun roof drains. Any ideas?