How to import GitHub issues and wikis to BitBucket?

I was also searching for a way to import Github issues to Bitbucket but didn't find one, so I wrote a script to do that: https://github.com/sorich87/github-to-bitbucket-issues-migration.

For the wiki, it's a Git repository that you can simply clone. https://github.com/blog/699-making-github-more-open-git-backed-wikis

Today we added proper issue import and export to Bitbucket. You can export an entire repo's issue tracker as a zip and then re-import on a different repo.

You can also create your own zips and so you could write very migration scripts to and from other issue trackers (e.g. GitHub).

Details: https://confluence.atlassian.com/display/BITBUCKET/Export+or+Import+Issue+Data

File format and data layout: https://confluence.atlassian.com/pages/viewpage.action?pageId=330796872