The Mac Pro is the powerhouse of Apple's computer lineup, a massive box which sits under the desk and is plugged into an external keyboard, monitor and mouse. Aimed at users who need more than an iMac can provide, it needs to be on the bleeding edge of technology. But after a speed boost in 2011, there's been radio silence from the company. That's not only concerning for the developers, visual artists, and so on, forced to contemplate trying to cram their needs in an iMac or MacBook Pro; it also hinted at a company unsure as to whether its future lay in computing at all.