So I took Keotag for a spin, very attractive and perhaps even useful for those needing to search for a particular subject by tag. Can’t really say that it did anything for me personally, but it did provide some nifty effects at least…

Keotag is a tag search engine, but it only searches one engine at a time. You enter a query and then see the results that that were tagged for the term on Technorati, Furl, Yahoo, and more than a dozen other sites, but not all at once.

The trick with meta-tag searching is to integrate and rank the results rather than segregate them by source. Even a tabbed approach by content type would be OK. As in returning tagged results for:
web | video | blogs | images, etc.

Providing a UI like Keotag is kind of helpful, but its not as helpful as Id like. To build a real meta-tag search engine requires some tricky indexing and a nifty ranking algorithm. As well as related search prompts, stemming, wildcarding, etc. You know, a meta-search engine. Source: The Search Lounge

[tags]keotag,meta-tag search engine,search prompts,stemming,wildcarding[/tags]