Another site that I had heard a lot about but never actually been to, Technorati was a bit overwhelming to me too. It's a great site to browse, though I'm not sure how you would go about finding one specific piece of information.
Looking at the "most favorited blogs", it's clear who is dominating this site. Site like "Pro Blogger", "Techcrunch" and "Lifehacker" are clearly designed for hardcore internet users. Probably people who make their living online. It's no surprise to me, the site is streamlined but not very pretty, so I can't imagine anyone coming here to just look around.
Technorati has been around for a few years now, so the concept of "tags" has traveled to many more sites since then. Blogger calls then "labels". Same idea, so they were nothing new to me. I love using tags on my livejournal, especially when it is something I write about a lot (harry potter, star wars, movies). It's an easy way to see all of your posts about that same topic without remembering exactly what day you posted.
This is a neat tool for a blogger though, as you can see how many people have linked to your site recently ("Technorati Authority") and see your ranking in Technorati. I'm going to pass on creating yet another watchlist that I probably will not use. You pick your way to read blogs and you stick with them - I prefer RSS feeds. And I think I'm at my limit of what I can read in a single day.