The final feature to be included in the upcoming release are CD Stubs. From the documentation page:
Many times people would like to contribute CD data to MusicBrainz, but would prefer to not learn to be part of MusicBrainz. These people would rather just toss some data into a pile and go on with their lives to listen to their music or rip their CDs. CD Stubs enable users to do just that.
With this release people who come to look up a CD, but MusicBrainz does not know about that CD, will be given a choice to either enter the CD as a CD Stub or to join MusicBrainz and to enter the CD into MusicBrainz proper. (This is the red pill/blue pill decision point). Note that users who are logged in to MusicBrainz when looking up a CD will not be given the option to enter a CD Stub.
To submit a CD Stub to the test server, use any MusicBrainz enabled CD lookup application to submit a CD to MusicBrainz. You must not be logged into the test server, otherwise you will never be given the option to submit a CD Stub. Then follow the instructions for how to submit a CD Stub.
To retrieve the CD Stub you must use the XML Webservice. CD Stubs are not available via the old RDF web service. Use this URL to fetch data for CDs that will also return CD Stubs if no CDs are available in the main DB:
http://%5Btest.%5Dmusicbrainz.org/ws/1/release?type=xml&discid=%5Bdiscid%5D&toc=%5Btoc%5D
This URL is also available via libdiscid and its example program discid.
MetaBrainz Blog 
Doesn’t seem to be working for me…
Great work on the new server features! I have a few questions about the CD stubs:
1. How can one see, edit and import existing CD stubs? http://test.musicbrainz.org/show/cdstub/index.html shows a list of all stubs, but you can’t see the details and you can’t import the stub into the main DB.
2. You can query for a stub disc ID like for every other release in MB, e.g. http://test.musicbrainz.org/ws/1/release/?type=xml&discid=aqI0USUSEX_kbzfDQS1SfRmy4ZU- . If there are both a stub and a regular release with the same disc ID which will be returned first? Is it possible to exclude stubs from being returned via the webservice?
@outsidecontext:
1. You need to be logged to be able to import either the release or only the DiscID of a CDStub.
2. A discid shouldn’t be shared by a cd stub and regular release. Each time a DiscID is linked to a regular release, the corresponding CDStub, if any, is deleted.
@murdos
2. I see. Still I maybe only want the webservice to return regular CD releases, not the potentially bad CD stubs. Just an idea.
jacob: What is not working? You gotta be more specific!
@outsidecontext: Webservice tries to serve regular releases before CDStubs (and don’t return boths)
And if you don’t return CDStubs, we can’t act as FreeDB and users won’t have any benefit in submitting CDStubs.
I really like this new system. It’s a improvement for both MB editors & users (ability to import CDStubs with DiscID rather than releases from FreeDB), and for anonymous user that will have an easy way to submit data.
First let me apologize for being critical. I’m currently benefiting a bit from using Picard and MB and apreciate the work that’s gone into them.
However, I have to say that after spending quite a few hours trying to figure out how exactly this all works I’m still puzzled.
What I’d like to do:
1. Tag a rather large collection of MP3’s. Most are ripped from CDs and therefore pretty well tagged from just using the iTunes lookup feature. What I really want help tagging are the “odd” things – downloads from artist web sites and things from some minor label CDs I’ve collected.
2. Help build the MB/Picard system by adding data from things I’ve spent hours tagging manually via lookups on Amazon, AMG, etc.
3. Understand the process. I’m not an average web user. I’m pretty technical. I have a degree in MIS, can code C, Perl, Javascript, and am very web savvy. Even so, after looking at the MB site and the seemingly redundant Wiki I can’t get a good picture of HOW THIS ALL WORKS. What is the process?
Every explanation I find is full of explanations like the one for CD Stubs: it’s highly technical (XML, RDF, etc.) and has a lot of “ifs, buts” and other conditional language. (e.g. if you’re logged in you can’t submit a stub)
4. I’d like to contribute quickly and easily. I’m not looking for a new committment. I don’t want to join the MB “community” – I already belong to enough volunteer efforts…BUT if I could push a button or two and contribute things that I’ve spent hours on for my own benefit I’d happily do so (and I’d love to benefit from others doing the same). I just spent at least 15 minutes trying to find out how to submit PUIDs using the “Submit PUIDs” button in Picard, only to find out that Picard can’t generate PUIDs along with a whole bunch of very technical explanations of why that is…and coming away frustrate by a button that seems useless.
If I can suggest some ways to help MB move forward they’d be the following:
1. Create a page that describes how the MB ecosystem works, how to A) use it and B) contribute to it (at different levels).
2. Get some press. Talk to a technology magazine reporter. They can help you COMMUNICATE TO THE MASSES. Not everyone who cares about music (and tagging it) is an OSS developer.
3. Try to keep things simple…both in the interfaces and in the documentation.
Consider this advice a contribution to the MB efforts. Yes, it may sound critical, but the reason I bothered is because I think you’re “on to something” here and have a lot of value you can provide in the future.
Best,
Croc