As of version 3.31, Movable Type natively supports tags.
Tags are keywords or descriptive terms associated with an item as means of classification. Unlike categories, an item can have many tags to describe the item in several ways. Tags are well known from other (web) applications such as Flickr for tagging photos and del.icio.us for tagging links.
The well known weblog search service Technorati introduced tags to weblog entries, and allows for browsing and searching texts on weblogs by tag. Blog entries can be tagged easily by simply placing a few links at the bottom of the entry in the right format: [tagname]
Now that MT also supports tags, I hoped for a fluent integration with Technorati. Even though the default MT templates do not link the tags shown on the pages to Technorati but rather to an internal tags search on the current weblog, I hoped for a standard implementation in the RSS feed templates spidered by Technorati. And indeed I found a correct looking code:
Technorati automatically converts categories in the RSS feed to tags, and even though MT defines a new namespace, it should work correctly… But unfortunately, the above code does not add the tag called “technorati” to the item, but rather the record number “31”. When I tried to look up the specification at http://www.sixapart.com/ns/types#tag, I received a 404, so I still don’t know whether Six Apart made a mistake when developing the new feed template or whether Technorati should have parsed the feed. Does anybody know whether either Six Apart of Technorati are working on this issue?