Apple CEO Tim Cook is on something of a PR blitz today. In addition to his extensive profile in Bloomberg Businessweek, he'll also be featured in an interview with Brian Williams on NBC's Rock Center tonight. Our own Joshua Topolsky will join Brian Williams in a chat right after the segment airs, tonight at 11:30pm ET. You can watch the segment live right here. Set your clocks for just about two hours from now, but until then, you can read our report on why Tim Cook, a notoriously quiet CEO, has suddenly become so chatty.