If someone types #hashtag, it should be automatically linked.
I'm of two minds on this.
One is that we've already got addressing outside the content area, so maybe it makes sense to do tagging there, too? Lots of systems (like Delicious, Wordpress and Flickr) do this for tags.
The other is that people like hashtags.
How about making the feature redundant (so: at both places)?
As you say people are used to it and would miss it as a new user
Well, I think the whole point of leaving it out is so it doesn't clutter up the content area.
Without length restrictions, it doesn't make sense to jam all the metadata into the content area. And it looks kind of blecherous.
I would opt to leave metadata as a separate field. I like intentionally linking, and auto-hashtags could muddle that up (I realize that an octothorp is used because it is unlikely to be used otherwise). Something I picked up from seeing folks mostly linking to Twitter stuff on other sites is to link @name and #hashtag to their respective pages on Twitter.
At any rate, I suggest we don't auto-link them. ^_^
One idea would be to allow hashtags in the text to cause metadata tags to appear automatically, but not linking from within the text itself, possibly even removing the hash in the text. So the tag field or whatever would be the official mechanism, but hashtags would be a shortcut.
I like how hashtags minimize the effort necessary to create data, just like CamelCase on the original wiki did.
I think in-text hashtags might have gone too far for us to ignore them completely.
Have the editor do the interpretation and drop the hash (preferably live as you edit - like the Facebook rerefence system)? I.E. the editor would turn #something into a hypothetical <a href="/tag/something">something</a>
I'm of the same opinion for @mentions
(I'm thinking info-bubble popups and such could be done by doing WebFinger discovery for an "activitystreams object" from the given URL)
Unfortunately identi.ca got less useful and fun without groups and hashtags.
Linked hashtags would be really useful to follow certain topics or events and would be helpful to find new interesting people.
Hashtags are essential for interaction and for discovering content. Without groups and hashtags, identi.ca has been virtually dead for me. The stream of information I get has dried up almost completely,