Want to see the upcoming 2012 BMW M5? Autoblog has the hookup. The V10 will be gone of course, replaced by the slightly less powerful twin-turbo 4.4 liter V8. Though this engine won’t exactly challenge the Prius for fuel-economy crown, it should manage a few more MPG’s than the outgoing V10. In the days of higher CAFE standards, every little bit helps.