Richard Wiseman, a known British psychology professor, is going to perform an ESP (Extra Sensual Perception) experiment using Twitter as the tool. The experiment will be performed in conjunction with the "New Scientist" magazine. The experiment "protocol" is described by Wiseman:

"At 3 PM (GMT) each day, I will travel to a randomly selected
location. Once there, I will send a Tweet, asking everyone to Tweet
about their thoughts concerning the nature of my location. Thirty
minutes later, I will send another Tweet linking to a Web site that
will allow everyone to view photographs of five locations (the actual
location and four decoys), think about the thoughts and images that
came to them in the 30 minutes before, and vote on which of the five
they believe to be the actual target location. If the majority of
people select the correct target, then the trial will count as a hit."

The trials will be held Tuesday to Friday this week (1st trial already ran).

My personal opinion is that this is a far cry from being any kind of a scientific experiment. To me it’s more like a publicity stunt by Richard Wiseman (granted, he’s a known person and might not want more publicity). I have run my own Psi Experiments a couple of years ago (site’s still alive). Experiment also presented an image with a choice of 1 of 5, where only one was correct. The skeptics (rightfully) criticized the experiment because it was so unscientific and the results of my first psi experiment showed that people are much more biased to answer options 2 or 4 out of 5 options present.

I believe even my 3rd psi experiment (still running) is much better designed.