Thanks all for the thoughtful comments. One additional angle on all this is the extent to which Twitter magnifies volatility/systemic risks (or not). I'll be watching this closely. Here are a few recent links for those who are interested:

http://tech.fortune.cnn.com/2013/04/24/should-bloomberg-be-afraid-of-tw…

http://www.nytimes.com/2013/04/29/business/media/social-medias-effects-…

(And a contrary view: http://www.howardlindzon.com/people-are-speaking-markets-are-reacting-f…)

What does all this connectivity mean for the investor? Howard Lindzon, co-founder and CEO of StockTwits, says it best:

"The news that affects the market is in everyone’s hands immediately with Twitter – so learn to live with this. I personally am standing further away from the pipe as ever, dipping in to the flow but not trading from it. I am constantly curating my streams for the people that provide the best context and most reliably deliver the best headlines. If you are ignoring it and day trading, you are really at a disadvantage going forward."

(Read more here: http://www.howardlindzon.com/who-really-caused-the-flash-crash-of-2013-…)