San Diego-based Stocktwits, the online, finance focused micro-messaging site run by Howard Lindzon, has a problem: Twitter just made stock tickers on the site clickable, replicating a major feature of Stocktwits. Stocktwits, which allows users to trade short messages around finance topics, has made its business to build a rich set of data and integrations around those stock symbols ($TICKER, ie $AAPL). According to Lindzon in a blog post, Twitter has "hijacked our creation of $TICKER", despite telling him a few months ago that that was "not a hole they wanted to fill." Stocktwits developed the idea of click-able stock tickers, allowing users to search for conversations about certain stocks on the micro-messaging site, as well as through partners like CNN Money, Yahoo Finance, and others. Twitter announced the feature this morning on its stream.