Link to March 18 New York Times article, "As Jurors Turn to Web, Mistrials Are Popping Up".
Excerpt: [Jury Duty 101.] Jurors are not supposed to seek information outside of the courtroom. They are required to reach a verdict based on only the facts the judge has decided are admissible, and they are not supposed to see evidence that has been excluded as prejudicial. But now, using their cellphones, they can look up the name of a defendant on the Web or examine an intersection using Google Maps, violating the legal system’s complex rules of evidence. They can also tell their friends what is happening in the jury room, though they are supposed to keep their opinions and deliberations secret.'