FORTUNE -- It was #TwitterRevolution at CNBC yesterday, due to the premier of @CarlQuintanilla's documentary on the micro-messaging service. And I was briefly involved in the pre-game, prognosticating about a Twitter IPO.
Part of the conversation was about Twitter's current value, which is largely in the eye of private market traders. On air I mentioned that recent sales had come in at close to $10 billion, while GSV Capital (GSVC) most recently had marked its Twitter shares at $9.8 billion. Since then, I've also received word from a secondary market source that some Twitter stock had changed hands at around a $10.5 billion valuation.
None of this, of course, necessarily means anything for Twitter's ultimate market cap. Companies are under no obligation to mark their public price above private trades. But it makes for good speculation as we wait for CEO Dick Costolo to pull the inevitable trigger.