The Raspberry Pi Foundation is likely to provoke a global geekgasm today with the surprise release of the Raspberry Pi 2 Model B: a turbocharged version of the B+ boasting a new Broadcom BCM2836 900MHz quad-core system-on-chip with 1GB of RAM – all of which will drive performance "at least 6x" that of the B+.Speaking to The Register last week, foundation head honcho Eben Upton said: "I think it's a usable PC now. It was always the case that you could use a Raspberry Pi 1 as a PC but you had to say 'this is a great PC...