I submit this into evidence of rampant human stupidity: https://twitter.com/NeedADebitCard
Never underestimate what people will do to try and feel special in their tiny social spheres.
With that said, there can be huge value in aggregating and correlating all social media commentary occurring in a specific area and around a set group of subjects. The bad guys will seldom reveal their activities on Twitter or Facebook but what others nearby are saying can help track them down.
Just to give an example in another sphere, social media analysis was very useful in tracking M23's mortar and rocket attacks on Goma during the recent flare-up in the Democratic Republic of the Congo, along with judging the success of the FARDC and United Nations Force Intervention Brigade counter-offensive.
It will always be limited of course, in no small part because very few people enable geolocation on their tweets and social media posts will never provide a complete picture of an event. But used smartly it does have some value.
No, but observers may be. Think Seattle WTO 1999...
Deep Web Intelligence? via Twitter? This sounds pretty delusional. Is the average criminal really twittering information about their crimes? Kids these days..