How about Wordpress?

Hi ntesla27. I'm actually surprised you'd want to sponsor this one, given we're just deleting stuff?

Re: Doc Natural - I think Wordpress already has a decent RSS export, which Composr supports (v8 supports RSS import quite a lot better).

Composr content types and their interchange support are as follows...
- banner, needs doing manually (it's unlikely very large long-term banner sets would want importing, because they'll be cycled regularly via some commercial contract)
- banner_type, N/A (Composr-specific)
- calendar_type/event, iCal
- catalogue_category/catalogue_entry, CSV
- cedi_page/cedi_post, no current method
- chat, N/A
- comcode_page, inbuilt support for htm files to be used as pages
- download/download_category, file-system and FTP based search
- forum/topic/post, we still have the forum importers and any other one can be done via intermediaries to those common ones
- gallery/image/video, zip files of media can be imported with EXIF detection for meta data and support for csv file for providing descriptions
- group/member, CSV import of members
- iotd, just import as gallery/image/video
- news/news_category, RSS/Atom
- poll, no current method
- quiz, quizzes are defined in text so are easy to input
- tester, no current method (this bundled addon will almost certainly become non-bundled in the future)

Also...
- emoticons, ZIP
- newsletter, CSV

Possible room for improvement...
- Implement cedi_page/cedi_post import (a zip of txt/htm files could work)
- Implement poll import (not sure what interchange format this could be)
- Comments/ratings have no interchange-based transfer method
- More consistent support for providing additional data for any content type within CSV, e.g. for downloads
(people can open up and sponsor issues for these if they need further development in those areas - for now it is more theoretical)