Technorati has taken a hit lately in the online press.

Their service had been unreliable.
Their search was full of splogs (spam+blogs).
Tags on your site gave them google juice.
Tags on your site gave them traffic.

However, as of late, some of these issues have been answered with speedy solutions. In fact, the service is now quite reliable [...]

The social aspects of web 2.0 are exciting.  And as the original social bookmarking and tagging website, del.icio.us draws a considerable user base (300K).  On Friday, Yahoo! bought del.icio.us for an estimated $20 million.
Launched in 2003 by Joshua Schachter, Del.icio.us uses a non-hierarchical keyword grouping system whereby users "tag" each of their Web bookmarks [...]