Over at Plasticbag.org, Tom Coates has an interesting hypothesis on the shift in tagging from a filing to an annotative process. Coates explains that tagging on del.icio.us was designed as a filing process while tagging on Flickr is much more of an annotative one.
While I agree with that argument, something occurred to me today that I found rather interesting. While posting to del.icio.us I thought realized that part of the reason it’s tagging system is more closely related to a filing system is because of the importance placed on the “extended” input box. For me, that is where I annotate my bookmarks, meaning by the time I actually get to the tagging them, there is no real reason to use the tags as a secondary form of annotation. The fact that you can search extended fields in del.icio.us only increases their usefulness and power as an annotation tool.
When you compare this process to Flickr, I think something interesting emerges. On Flickr, you can place notes on a photo, however, this is not a primary activity. One look at the Flickr interface and you realize that adding a note to a photo is a secondary process, something that can only be done once the photo is uploaded and clicked on.
There’s a difference in the user experience of tagging across the two sites that can’t be denied. It’s quite possible that people are beginning to use tags in a more Flickr-ized/annotating way on del.icio.us (as Coates suggests by the shift in the tag “blog” from “blogs,” the singular being an annotation versus the plural being a category). However, I would tend to believe that we will continue to see a large difference in the way tags are used across both sites thanks to the interface design.