AMG is working on the B25 for 2012. Starting next year, AMG, the Mercedes-Benz performance division, will start releasing performance-rated versions of smaller Mercedes models and not just the big and expensive ones, such as the ML63 AMG that we saw recently.This means the smaller A-Class and B-Class models will be available with some hotness under the hood.Case in point: our spy photographers have just caught the Mercedes-Benz B25 AMG testing. Based on the A25\'s platform, the B25 AMG will run on a turbocharged 2.0-liter engine with direct injection which puts out some 320-350hp to all four wheels via a dual-clutch transmission.Visual changes still appear to be minor, with a different front-end which includes a revised bumper and bigger air intakes. We also suspect a slightly different rear bumper with a diffusor, however with all the camo it\'s hard to tell. Bigger brakes with bigger wheels basically finish up the AMG package.What\'s still up in the air is if the A25 and B25 will get the trademark AMG quad exhaust pipes.  It\'s possible AMG will keep those in reserve for the bigger Benzes and let the smaller vehicles wear only two slightly bigger ones.The Mercedes-Benz B25 AMG will be released next year.Photos: CarPix