Bitcoinica's web server is hosted on rackspace (through Heroku). They would likely have been able to determine that bitcoinica's bitcoin daemon was hosted separ

Bitcoinica's web server is hosted on rackspace (through Heroku). They would likely have been able to determine that bitcoinica's bitcoin daemon was hosted separately on linode, by watching the ip addresses broadcasting withdrawal transactions. It is likely that bitcoinica was the target in breaching linode.