and I'd like to get a few more eyeballs on this to make sure it works.So:
To be clear, this doesn't enable you to do anything that couldn't be done with quakelivedec. It just makes the process of working with Quake Live pk3s a little nicer.
If you're already familiar with 7-Zip, the elevator pitch here is: "anything you could do with zip files, can now also be done with pk3 files."
Here's an example of one method of creating a Quake Live pk3 and then opening it up for inspection, using the Windows Explorer integration of the 7-Zip File Manager:
That really is a Quake Live pk3 that you could drop straight into baseq3 and use, without needing to run it through quakelivedec.
More details, download links, and source code at http://neogeographica.com/site/pages/tools/7zippk3.html (Windows only, sorry!)
I've only used this on the systems that I have here at home, so although this is a pretty simple change to 7-Zip it's entirely possible there could be some problem... let me know if you run across any oddness.