Per Michael Arrington’s request I ran backstage and shoved a camera in CitySourced’s founders’ faces just after they completed what was one of the more compelling presentations of the day. Question one: Palm is really paying companies to write apps for the Pre? Yes. How much? All I got despite truly obnoxious questioning was “under $500,000.” (If you’re a developer and you have a better answer, leave it in the comments or send to tips@techcrunch.com.) We also talked about the biggest execution risk: Whether or not cities will actually use this data to make citizen’s lives better? Gavin Newsom : I hope you’re paying attention to this.

Sentiment detection is fast becoming a popular method of deciphering Tweets, news stories and other content on the web. TechCrunch50 startup Affective Interfaces, which launched at the Business Applications session today, has built emotion sensing technology that detects a web user’s facial expressions via a webcam. Affective Interfaces’s SaaS uses a webcam to monitor facial expressions such as smiles, frowns and other emotions. The software analyzes these expressions and how they related to different parts of a site.

Yesterday, at 4:30pm, after a long day of demoing oDesk in the TechCrunch50 DemoPit, Michael Arrington dropped by our table to inform us we won an Audience Choice Award and a chance to demo on stage to all 2,000 conference attendees.  We were already thrilled at the warm the reception our product had been getting all day, but this was a truly spectacular opportunity and a great way to end the day. Here’s the demo our CEO, Gary Swart, gave.  The panel of experts consisted of Marc Andreessen, Roelof Botha, Paul Graham, Tony Hsieh, and Marissa Mayer.