stockhouse is good for canadian stocks (canadian stock markets are surprisingly active, plenty of interesting small stocks).
Quote from Alpha7Trading:
You can also try http://trade2win.com - http://www.wallstreetoasis.com and http://www.prop-trading.com - all excellent sources
Quote from billyjoerob:
One thing that's bad about twitter, as another person said, it's basically one way. There's a small number of people who have 10000+ tweets and all talk to one another, otherwise you're a homeless stalker talking to yourself.