I have heard of Technorati, but I haven't really used it very much. I know what it does (blog searching, surfing popular tags on blogs, seeing what bloggers are writing about right now) but I never really had a reason before the challenge to explore it very much.
The front page is a bit overwhelming, although it looks a lot like a regular online news site, like cnn.com or yahoo.com. It's interesting that there are lists at the bottom of the Technorati front page of news articles and blog posts that are rising in popularity. It would be sort of interesting to take an afternoon and watch the popular items for a few hours, just to observe how it changes over time.
After doing a quick search for Learning 2.0, I found quite a few blog posts and actual blogs devoted to 2.0 and web stuff and libraries and learning. I like the ability to see tag clouds for each blog that comes up; it helps you get a better idea of what type of blog it might be before you go to the trouble of clicking on the link. (We are growing so lazy, aren't we?)
Then, I looked at the Popular page, and that seems fairly straightforward. Interesting that "web 2.0" is the number one search for today! Are there other Web Challenge folks catching up on last week's post as I write this? You never know. The internet is a pretty wacky place.