GM stated that by 2014 they wanted to cut 50% of their vehicle diversity. Meaning they wanted to cut down how many engine went into each vehicle and build different vehicles on the same platform in a since cutting r&d costs in half. What we have been dealt is the 3.6l which is in the Buick enclave, Cadillac SRX, Cadillac CTS, Cadillac ATS, Cadillac XTS, Buick Lacrosse, GMC Acadia, GMC Terrain. The 4 cylinders are poplar because recently we have been able to crank a ton of power out of a 4 cylinder and still get respectable gas mileage. Take the Buick Regal GS, it's a 2.0L turbo cranking almost 270hp. GM is achieving the goal that they have set out to do. Remember every Escalade you see 3 small cars with little motor have to be sold to offset their balance with government. Other wise at the end of the year GM get nailed in penalties for not meeting the avg mpg for thir fleet of vehicles.
As a true motor head and bass head I do not like to see what is going on with the motor choices, but there are enough people in government that can make a lot of money on taxing people that for instance sign up for the gas guzzler tax when buying a guzzler. And enough people are concerned about the environment that true motor Headz have to stick to building old cars with new crate motors!
Sorry for the rant but I work at a dealership that sells GM products and I see it everyday!