Crash, by definition, is something there's no early signs of. Today's dips are someone selling their coins. When everybody wants to sell coins and nobody wants to buy coins, you get a crash. Obviously enough, some people bought out coins which were sold today.
PS I like how you completely stole design from coinbase, way to go! Solid and sound business idea there. Just like your posts.
Coinbase's whole layout is using the default Twitter Bootstrap interface...
http://twitter.github.com/bootstrap/