How does the Launchpad "published" acroread package relate to the main Ubuntu repos?

You can browse the repos via the internet from any of the mirrors for that particular one you could use: http://us.archive.ubuntu.com/ubuntu/dists/jaunty-proposed/

And if you want to "clue" yourself in, insted of giving you an answer I will give you a "riddle":
I am the "master of the universe" but I'm not He-Man... Who am I?

I know it sounds stupid but it's easier than it seems...

Hope that helps!

Y'know, I might be having one of those days, but:
"Yeah, because `zgrep`ing dozens of tarballs is the most convenient thing ever?"
[Is.. is this what other people actually do? Or it's possible that I've completely missed the bus as to 'browsing' without 'adding to sources.list', which would be why I'm *asking*...]

Also, dereferencing your pun ("I am the very master of the master repository, I mirror to other masters that mirror my mastery, and on each of those mirrors mirroring my README, you'll find the string declaring they're the master repository..." ♫*) was inconvenient when it wasn't even clear which aspect you were trying to address with it - we could both have saved some lifetime if you'd just linked http://wiki.ubuntu.com/MOTU - which is not exactly concise or navigable as to the relation between Launchpad and the repos.

* /That/ is not actually a problem, thankfully - though it certainly clogs up my Google results. But two can play at this game. ;)

Anyway, I seem to have answered my own question in this case by discovering that 'partner' is, in fact, an "official" repository, somewhat inexplicably barred from the 'Ubuntu Software' tab in the GUI when both the restricted drivers and the Multiverse's probably-not-legal-in-your-jurisdiction packages are: https://help.ubuntu.com/community/Repositories/Ubuntu
...This explain what Launchpad has "published" to (the "partner" repository) and how (it's a U-- oh, wait, *cough,* Canonical -- repository, which explains why I had no idea it existed). I was staring at the string 'partner' earlier wondering "What does this *mean?* Is that a repo or does it mean it was handed back to Adobe for distribution?"

Admittedly, the existence (and 'favored-nation' status, since it's not 'Ubuntu,' but it /is/ from.. well, you know) of the 'partner' repo would be more obvious on a fresh install not cluttered with dozens of other disabled sources.

...now if only PPA packages could be tracked for updates without cluttering the sources.list, and apt-get and its frontends (particularly update-manager) were better at showing which repo a new dependency is going to come from before it's installed (that whole model is wrong - I don't want to trust everything in the PPA, just the packages I explicitly need from it!) ... but I'm getting pretty far afield here!

ooooohhhh!!! So THAT was your Question!!!

It's true I could have answered quite more simply but, I think that I am the one having one of those days... after a 6 hours in a row concurrent programming class you could find your self speaking in Fārsi (If you know what I mean...), so... my bad =)

About that all that 'zgrep'ing... I don't think it's the most convenient thing to do, but it's definitely the most creative way I've ever heard of! Personally I would have opened synaptic package manager, add 'proposed' to sources.list and then use the left hand filter to look up the packages and the descriptions after all then you can just "turn them off" and don't use them (But your way seems more entertaining!)

About the motu thingy (by the way your pun was awesome!) I thought you wanted to know how do packages came to be into repos... but I feel obligated to point out that it was your idea to use the phrase "clue myself in", I just pointed my finger in the *ejem* "right" direction (maybe the easiest... perhaps not the most effective... definitively not shortest... but direction nonetheless...)

On that last paragraph I agree, I also think that the model is "wrong", but I think the reason this is done this way is because is easier to assume that IF you add a new source is because you trust it. In any case you are given the choice not to update.

I would continue writing, because it seems almost rude not to do so, considering the quality of your response, but quite frankly I'm falling a sleep over the keyboard, and at any rate...

The important thing is that you managed to find and answer to your question!
even with my misleading and "partially incorrect" answer ;)

So I say goodbye for the present. (And I promise to be more helpful the next time!)