StockTwits.com is a real-time stock conversation.  When a user follows the @StockTwits bot on Twitter, they can give an opinion about a specific stock symbol through a Tweet.  The tweets will appear alongside the StockTwits.com profile of the stock symbol.  Therefore you can compare what is happening to a stock and compare the Tweets next to them in real-time.  All of the information is archived too. 

Below is a screen shot of how it works: