On second thought, I guess that is what the CouchDB guys are/were doing, but I don't think the whole picture has come into focus for anyone yet. It will quite something once it does.
Are there general topics people would be interested in for hackathons that would be more interesting? I'd like to see more "hackathons for good" like http://cure.nyhacker.org or interesting topics like http://gamehackday.org
Some comments:
4. Centralized subscription manager.
If we're talking RSS, nearly everything syncs with Google Reader at this point. I'd love for that protocol to be opened up...
8. Open source Dropbox clone.
This would be awesome, especially with Dropbox's history of design related security issues.
11. Make Apache an end-user product.
WAMP/MAMP and similar are one step in this direction.