Tom Coates has a great post over at Plasticbag that deals with the difference between del.icio.us-style tagging (filing) vs. Flickr-style tagging (annotative). This overly long excerpt lays it out (emphasis mine, urls redacted):

Matt Webb and I did a fair amount of work around tagging with a project called Phonetags that I never get time to properly write up. As we were working on it, we came to realise that each of us had a radically different understanding of what a tag was. Matt’s concept was quite close to the way tagging is used in del.icio.us - with an individual the only person who could tag their stuff and with an understanding that the act of tagging was kind of an act of filing. My understanding was heavily influenced by Flickr’s approach - which I think is radically different - you can tag other people’s photos for a start, and you’re clearly challenged to tag up a photo with any words that make sense to you. It’s less of a filing model than an annotative one.

When I came to use del.icio.us I approached tagging in the way that made sense to me from Flickr. So any and all links were covered with loads of keywords with no thought for how they ought to clump together. I just tried to describe what the link was about in some way. Joshua and I had a bit of an argument about the way I was using it, actually. The browsing interface didn’t really suit an approach that had an enormous number of orphaned tags. You can get a sense of how out of control it all got with this visualisation of my tags. At the end of the argument I said to Joshua that it was almost like he was treating tags as folders. And he replied, exasperated, that this was exactly what they were. It was just that now an object could exist comfortably in a number of folders so you didn’t have to enforce an arbitrary heirarchy on your filing…

So two radically different forms of tagging that really share very little in common with one another - which leads to the question, is there room for two different paradigms here (at least) or will there be some refactoring and adaptation that moves us towards one or other model?

Then, by looking at how people are tagging his weblog Coates proposes a hypothesis: “the shift from people using blogs to blog [as tags for Plasticbag] represents the increasing dominance of a Flickr-style paradigm of tagging… It is my conjecture, therefore, that the folder metaphor is losing ground and the keyword one is currently assuming dominance.”

What do you think? I suspect people are mixing methods already–using some folder-type tags (e.g. toread) along with other annotative ones.

The whole post is well worth the read–for the graphs and the novel thinking about tagging (finally!).

Carolyn Minor, a librarian at the University of Winnipeg, has put out a call for help on event tagging. She’s noted the difficulties in setting up effective tagging for event blogs, which is something I struggled with myself in setting up the event blog for the 2005 Online Deliberation conference.

The main problem I ran into is that I have yet to find an accessible and effective tool for tag-based searching of blogs. For a brief and beautiful moment I thought Feedster was capable of searching blogs based on a field, but no dice. And of course Technorati has yet to add RSS feeds to its tag pages, so that’s out. So the only currently viable approaches are:

1. Keyword searching: Choose a tag that is a unique keyword — something not already in use on the net, like the OD2005 keyword we used for Online Deliberation — and ask people to use that keyword as their blog category for posts they want aggregated into the event blog. Then set up a keyword search in something like PubSub, and aggregate the resulting feed into the main event blog.
2. Blog-specific aggregation: Ask event participants to use a specific category title for posts related to your event, and to submit the URLs for their existing blogs. Then subscribe to each individual blog’s RSS feed from within your event blog’s aggregator, but set it to only aggregate posts whose category matches your designated tag. (If you’re a WordPress user, you can do this using FeedWordPress.)
3. Technorati yourself: If you just want a place where you can all find the photos and blog posts you’re tagging, you can tell people to visit the Technorati page for the tag you’ve chosen. It’s not a great solution if you’re trying to build a site and community, but it’s an ok approach if you’ve got a group of people who just want to keep vaguely on top of their shared interests.

Of course these options just address the technical challenge around tag aggregation. They don’t touch the more fundamental problem, which is that it’s awfully hard to get people to do collaborative tagging unless they already blog, know something about RSS, and know something about tagging.

My own solution to this dilemma is to treat event blogging as an opportunity to ease people into the world of blogging and RSS by encouraging them to set up accounts on the conference blog itself, so they can post from there. I also set up e-mail-based aggregation so that people can submit photos and blog posts by e-mailing them to specific e-mail addresses, which then get aggregated into the site. That gets them into the swing of things and perhaps gets them interested in setting up blogs of their own.

In other words, figure that outside (and maybe even inside) of events for bloggers in particular, you’re not going to be able to make a go of a tag-centred event blog. But you can build in a bunch of other aggregation options that let people participate in less-techie ways, and include tagging as an option for the tag-savvy few.