Last month, someone (from the US Navy, actually) wrote me to check on the status of my stable versions extension. I told him it basically should work, but has never been tested in a live environment. He got it to work (on a 1.6 MediaWiki) and tells me "everything is working fine", with some minor hacks he made, and which I checked into SVN for him. There is an issue with caching, though, which will prove to be no real obstacle but just a little work to fix it.
Sadly, I didn't have time to come to Wikimania this year, but I listened to Jimbo's opening speech today. I was very pleased to hear that finally, we're going to get stable versions, and as a German, I concur that de.wikipedia is a perfect testing environment for this (we've banned all non-free images, and stubs; stable versions are the logical next step). I also agree with Jimbo to just start with the simplest possible solution, see how it works, and modify it from there. Releasing software very early has been my motto from the start, much to the pain of our CTO ;-)
Anyway, I'd like to know if there'd be a point in me fixing the caching issue. Brion, will you roll your own implementation, or use mine? If it's the latter, should I apply final polish to it so you can get single login up and running first?
Apart from that, some general thoughts:
While the "simplest possible solution" would, of course, be another field slapped to the page table, it seems to me that any expansion from there (multiple stable versions, different kinds of stable versions - vandalism-free to peer-reviewed, etc.) will end up using its own table.
Should there be a new group of "stable version editors"? Should these be initially identical with admins to give it a kick-start? But that would already be covered with the code we have, right?
Don't forget to implement "oldid=stable" to return the stable revision. What if there's no stable revision? Return a blank page, a note, or just the current version?
Who's gonna see the stable version, if there is any? Anons, of course. What about the google bots? Probably the same. And new users? Yes, to prevent culture shock ;-) And add a user option to change that. Current users, however, should have the "show stable version by default" option turned /off/ by default to keep the current behaviour working. Least surprise, right?
Oh, and, of course, an additional dump with just the stable versions instead of the current ones. Also a "mixed" one, with stable version if existing, and current ones otherwise?
There should be a special page to list pages * with stable versions * without stable versions * pages with stable version, sorted by how much time/how many edits/mor many bytes are the difference between the stable and the current version
So much from Germany, and have fun at the last Wikimania day, Magnus