It doesn't seem to work for me. I tried to create an archive for all my data and it just shows 'Files: 0, Size: 0B' on everything.
Edit: Tried a second time and it works now.
But as it was said, the most important thing I miss is a way to extract the mails (in the way they are stored in GMail with all tags and other meta information).
Tags are the most important thing for me. If this is not possible, any extracting is really not worth it for me.
To extract tags right now, you could search in every other directory (and assume that this are all available tags) for the same mail and get by that error-prone algorithm all tags of a message.
Maybe also missing is some meta information about the spam level and/or importance level. And meta information why Google thinks that some message is important to me (on the web interface, it sometimes shows a reason like 'because of recent conversation with this person' or so).
And maybe more. I would just like to get everything.
> et by that error-prone algorithm all tags of a message.
Shouldn't be error-prone. All your emails should have a Message-Id: header. While not impossible, I've never heard of issues due to Message-Id collisions...
You could write something to sync your emails to a database, then when it encounters an email in a 'folder' it can just add it to the email as a tag. I don't know of anything that currently does this, but it's not like the technology (and information) isn't there.
> And meta information why Google thinks that some
> message is important to me (on the web interface,
> it sometimes shows a reason like 'because of recent
> conversation with this person' or so).
Of what use is this outside of Google, though? IIRC Google is the only one doing something like this. It's not like you could import that meta information into Outlook/Thunderbird/Mail.app.
Error-prone because it adds stupid complexity and many additional steps for just getting some simple information which Google probably has stored already along with the mail. With additional complexity, you always get further things in your algorithm which could go wrong. Such unnecessary complexity should always be avoided.
Edit: Tried a second time and it works now.
But as it was said, the most important thing I miss is a way to extract the mails (in the way they are stored in GMail with all tags and other meta information).