News Roundtable! Twitter turbulence, FB-YT video wars, prez hopefuls courting/alienating SV,

News Roundtable! Today joining Jason is Ben Parr (investor @dominatefund, author @captivology, ex- @mashable @cnet) and Declan McCullagh (founder, recent.io, ex- @CBS, @CNET, @Wired, @Time). Twitter lows and highs. Troubled stocks and a leadership vacuum ... but its latest feature is a shot across the bow for all news apps. State/future of media, Hank Green vs. Facebook video vs. YouTube, dish on current crop of prez hopefuls courting and alienating SV, Jason tweeting Jeb Bush, hacking and protesting in China, smart gun tech, cyberattacks, U.S. gov't building supercomputers, Jason's intentions…