Digg.com had very recently introduced Digg toolbar or DiggBar as a new ULR shorting. Earlier Digg.com have a good repute of book marking services.
Today Jason Kincaid at TechCrunch reported the failure of diggbar as “DiggBar Commits Career Suicide, Starts Redirecting Users To Digg Homepage”

Digg’s URL shortening service DiggBar has been marred with controversy,
though things have mostly died down over the last few months. Now it
looks like Digg has made a change to the service that will alight the
web’s flames of fury anew, and this time their actions have moved from
irritating to downright shady.

Read more about this at TechCrunch blog