I posted a beta version of the lipsynch editor
we're using on PCGameMods, in case anybody else might find it useful.
It's Java-based and requires JRE1.5. (Theoretically it should run under 1.4.2, but one of the Swing components seems to cause spontaneous crashes in 1.4.2.)
Basically it lets you open, modify, and save .lip files. You can copy/paste entries between files and delete time slices. I find it useful for updating a .lip file after modifying a sound file (cutting a word out, etc.).
There's also a description of a somewhat convoluted method of generating a new .lip file from a .wav sound file and a text transcription. (Extra download of a toolkit required, link included in the readme). The results aren't perfect, but it's faster than creating a new .lip by hand.
Feel free to post questions/comments/bug reports/whatever, but updates to this are going to be a fairly low priority for me until our mod project is complete.
Source code is included.