You can't delete the file, since it's locked via firmware. U3 Drives have extended functionality for Windows systems, and LaunchU3 is the autorun launchpad to support these features. Since people apparently love to delete things, the launchpad is firmware-locked to prevent accidental removal.
U3 is not supported on a Mac or *NIX system, so it will function like a regular USB flash drive in these systems.
There is supposedly a way to remove the "smart" partition via a link at
http://u3.com/uninstall/ but I don't know if this is a list of removal instructions or a file you download and run (which also wouldn't run on a Mac.)
-Z