A story about Startups can belong in multiple subreddits, eg: r/startups, r/entrepeneurs, r/business.
If a story had tags and there was a system where the frequency of tags appearing in a subreddit mattered it would allow me to look at r/startups and then find the other subreddits relevant to my interests.
reddit made the mistake of treating every subreddit as its own individual isolated community without considering crossovers in interests. If tagging existed then this would not have been a problem. Today 6 years on it's still impossible to find good subreddits relevant to specific interests, tags would have been one of the solutions for that.
The reddit founders talked and thought about this tremendously, and ultimately decided that it was more important to have distinct communities, so that the same story can be on /r/aww and /r/photography without one group overrunning the other. Or /r/TwoXChromosomes and /r/MensRights. Or /r/politics and /r/economics.
I think that this was one of the most important strategic decisions in reddit's history, and that they got it right.
I'm not saying tags can never work, just that any proposed tags system needs to supplement, not destroy, the siloing of subreddit communities. And be simple to use, even for the 99% of redditors who never even vote or subscribe to anything.
I was strongly opposed to subreddits when they were proposed. I thought tagging, like Delicious did, would be a better solution.
I'll happily admit that tagging could not have grown Reddit to anywhere near its current size without the site collapsing on itself. The different feel to each community (compare F7U12 are AskScience) is much more appealing than a single homogeneous group. However, I think that it was the first step towards breaking the promise to create an personalized news aggregator. I for one was disappointed when the recommended posts feature was dropped.
The initial missteps with whitelabel sites like the Wired-branded reddit and lipstick.com are amusing in hindsight. I'm not sure how reddit with a pink background with Courier as the primary font was supposed to attract a female audience.
My idea of how tags work would be on top of subreddits. Subreddits are a fantastic idea and make reddit reddit but tags would work along side that and a way to associate stories with multiple subreddits.
For example, if a post could be tagged "startups" and was posted to r/business, when I tried to find other subreddits besides r/startups about startups I could search "subreddits with x or more stories tagged "startups"" and I'd be presented with r/business.
They wouldn't exist as a replacement for subreddits, they'd exist along side and serve as a way to connect subreddits by topic. Subreddits currently exist as their own entities with no crossover which doesn't work well for expanding a users subscriptions to other subreddits relevant to their interest.
They would be useful for something like what stackoverflow does by allowing people to block tags or highlight others (e.g. Block Ron Paul posts in /r/politics).
That said don't listen to me. I have quit using reddit, except for /r/gonewild.
Negative filtering would be a disaster. The power users do most of the voting and almost all of the reporting. If they all could block Ron Paul, those stories wouldn't get downvoted and, when offtopic, reported. This would cause the Ron Paul stories to take over the site for the 99% of users who wouldn't be using the filter.
You can link the same post as a reply to multiple items. This allows for complete flexibility. Posts that are relevant to more than one section can live in each of those places
Oh, so you're saying tags in addition to the subreddits, but tags don't cause posts to show up in subreddits. I think that could work, but I'd be most wary of burdening down the poster with selecting tags or distracting people by having them "vote" or suggest tags.
Make it so that tags are suggested only from the page where you can see the comments and that no tag show up unless $NUMBER users have suggested the tag (so arbitary tags aren't developed). Allow users to vote on public tags. If you suggested a tag that gets downvoted, you lose karma.
That's close to the system I would advocate. But it's hard to get something like that right, and until this past year, reddit never had the manpower for such a huge project.
If a story had tags and there was a system where the frequency of tags appearing in a subreddit mattered it would allow me to look at r/startups and then find the other subreddits relevant to my interests.
reddit made the mistake of treating every subreddit as its own individual isolated community without considering crossovers in interests. If tagging existed then this would not have been a problem. Today 6 years on it's still impossible to find good subreddits relevant to specific interests, tags would have been one of the solutions for that.