It was due to be launched in January 2011, but a video of the new 2012 Mercedes-Benz SLK leaked onto YouTube last night before being taken down shortly after. The lengthy promotional film shows the folding-hardtop SLK in detail, highlighting some of its new features including the NECK-PRO head restraint, adaptive lighting and ECO stop/start system.

Mercedes are making a big play on the increased safety of the new SLK, saying that it will set new standards for open-top sports cars, new systems such as ATTENTION ASSIST which detects when the driver is drowsy and provides an early warning of overtiredness, the optional occupant protection system PRE-SAFE® and PRE-SAFE® Brake, which can apply the brakes autonomously in the event of an impending front-end collision.

We’ve captured some screenshots to save you sitting through the full 9-minute video, but we suspect Mercedes may be forced to launch the SLK earlier now that the cat is out the bag. The styling seems evolutionary, adopting the front-end design of the SL together with updated lighting and wing mirrors.

No further details have as yet emerged, but expect to hear something officially from Mercedes-Benz soon.

2012 Mercedes-Benz SLK is unofficially unveiled - expect further news soon.

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