links for 2009-06-09

• Orphaned Tweets
  60 percent of Twitter users do not return from one month to the next. Both findings suggest that, thus far, Twitter has been considerably better at signing up users than keeping them.
  (tags: twitter performance duration)
• Aphalt Spot
  One way to make parking lots more interesting…
  (tags: parking urbanism art public_art)
• “Call for Art Historical Knowledge”