Del.icio.us was an early bookmarking site, that began in 2003, was bought, mismanaged and sold by Yahoo, and then relaunched under new owners in 2011, arguably after its moment had long passed.
At its height, in 2008, the service claimed more than 5.3 million users and 180 million unique bookmarked URLs. The site had three urls. The first two were amusing (but difficult to remember) hacks around the .us domain: de.icio.us and later delicio.us. The third (and current) domain is delicious.com.
In September 2005 the site looked like this:
In February 2008, it looked like this:
Today, January 30 2013, it looks like this:
The middle image shows Del.icio.us three years after they had been bought by Yahoo. Clearly, whatever Yahoo did or din’t do with the site, they didn’t spend a lot of time or money on its design.
A much fuller history of the site is available at Wikipedia.