I don't mean to be critical or anything, but I don't understand why this would need to be 64-bit.

One of the things I can see happening with Leopard out is people getting unnecessarily hung up on apps being 64-bit, when it's really only needed for accessing large amounts of memory (>4GB) or handling massive datasets: http://developer.apple.com/macosx/64bit.html

All Lingon does is build small plist files, like, <5KB, and load and unload them out of launchd.