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With all the issues migrated to github, we really should update the documentation to send users here instead of to trac. I would argue that this should be done prior to release, so that all the people using the shiny new 4.0 won't get frustrated with the fact that trac is read-only.
Rather than muck with the docs right away (i.e., before the release), perhaps it would be easier (for now) to make trac.parrot.org redirect to github for a little while. If someone really needs to access trac, it could be via another URL.
If we want to push the release back a week, I can probably get 'er done (or help mortiz). If not, then +1 on @perlpilot's suggestion. (But I don't have the authority to accomplish it.)
The github-links branch has a lot of updates to various links in the source and docs. Notable omissions right now are tickets, docs/submissions.pod, and some random unmoved wiki pages.
When I said "prior to release" I failed to notice the release was supposed to be today. It may not be important enough to wait. I'll leave that up to whiteknight to decide.
This was mostly taken care of by moritz. There are some URLs to trac still, but they're mostly old wiki pages and closed tickets. These can probably be left there. There's still references to open tickets, but that's already open as #707.