I also think hash tags could help in another area: commit comments. It's something important I've mentioned before, and I think hash tags can be useful in commit comments even if there aren't any tools yet to mash it up. A few days ago, our of habit I accidentally started including some high level hash tags in an svn commit comment and it occurred to me that it might be useful to others, if not myself in 6 months. If we find hash tags useful in yams and tweets, why not commit comments?
Including tokens in commit comments isn't new. In fact, we already include a Jira number in most of our commit comments and this allows us to view all the commits for a Jira issue. There is even a Jira plugin that allows you to perform actions by specifying hashes in commit comments. For example, if I want to resolve a Jira I can include #resolve in my commit comment, and Jira will automatically Resolve that Jira. And don't feel like you can't include the #resolve tag only if your using that jira plugin. I could see value in seeing a #resolve tag in the final commit of a Jira.
As an example, here is the exact commit comment I used that includes some hash tags for geoserver and installer.
"Jira: AC-4207. Got the filtered geowebcache.xml file correctly moved to the production and staging data directories. These files point to localhost with the correct geo port and stage geo port. Also commented out some fixpath.cmd lines to get the installer to work. Finally, I also change the ProcessPanel to not have a condition:
Now the really cool part is if someone else in the near future notices an issue with geoserver in our installer, this comment will stick out more than a comment without those hashes.
Another cool thing that could be done is a team subscribing to certain hash tags in the svn commit emails. For example, someone responsible for peer reviewing all DAO changes could subscribe to a hash like #dao. Then when developers are modifying DAO's all they need to do is include the #dao tag.
I guess what I am saying is perhaps we could also benefit from putting extra hash tags in our commit comments. My brain has already been trained to read them so personally I think it's useful.