Just joining in on the conversation here....
I'll have my TCH exactly one year at the end of November. I park my car in the garage every evening. On at least three occasions and quite possibly as many as five, I've gone into the garage in the morning and found the trunk open. I honestly can't rule out accidental key press while I transfer the FOB from my pocket to the place I keep my keys in the house...but I also can't rule out something else is going on here...because it does require a long time of holding the button down before the trunk actually opens. Also, this mysterious trunk opening has only occurred while at my house in my garage.
To pacify myself, I've rationalized it *must* be due to an accidental key press, but now that I see this thread perhaps something else is going on...or at least the I'll be paying much more attention to how I handle the smartkey FOB.