You never know for sure what moves a stock, but increasingly social media, especially Twitter and its cousin, Stocktwits, is playing a bigger role in daily market moves.

The most recent: J.C. Penney .

Its stock started popping at around 1:57 p.m. ET today, shooting up as much as nine percent on no apparent news.

Then I checked my twitter feed and saw this from @markflowchatter, who generally has good radar:

JCP spiked at 2pm when fashion expert Nina Garcia mentioned she met w Ron Johnson at JCP HQ and is calling the new prototype a "gamechanger"

And then there it was, 49 minutes earlier, in a Twitter verified tweet:

@ninagarcia: I'm @jcpenney's HQ. Thank you Ron Johnson for the walk through of JCP's prototype. Get ready to shop! Its going to be a game changer!

Never mind that Penney announced a week ago that it had partnered with the Project Runway judge to become its “resident Style Voice and fashion collection curator.”

I went on air with Brian Sullivan on "Street Signs," and in an otherwise J.C. Penney news vacuum, cited the tweet.

Among the tweets that followed:

@firstadopter: Umm Nina Garcia might be a little biased since $JCP IS PAYING HER! @markflowchatter @herbgreenberg

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