Crossovers of all shapes and sizes are a sizzling market segment. Buick has two respectable ones in the subcompact Encore and the full-size Enclave, but the two models could not be farther apart in size and pricing. We actually felt it would have been more logical to introduce a higher-volume midsize model based on the Chevrolet Equinox before debuting the diminutive Encore.

Well, it looks like Buick has finally come around to seeing our line of logic. These spy photos show an intermediate-size crossover with some of Buick's signature styling cues, most notably its vertical grille strakes and circular center badge, as well as sculpting of the fenders and doors that bear a strong resemblance to the larger Enclave's.

The proportions indicate a vehicle slightly smaller than the current Equinox and Terrain, which are closer in size to the Ford Edge than the compact Escape. The Buick "Anthem" as it's rumored to be called (although we would have expected a name starting with an "E" to keep Buick's crossover naming convention consistent) will also face the Escape-based Lincoln MKC when it's expected to hit showrooms in mid-to-late 2014 as a 2015 model.

In terms of power, Buick's midsizer, whatever it's called, could be all four-cylinder. The current 3.6-liter V-6 in the Equinox produces a near class-leading 301 hp and 272 lb-ft of torque, but its 17 city/24 highway fuel economy rating is near the bottom of its class. Some good candidates are GM's direct-injection 2.0-liter turbo I-4 which produces 259 hp and 295 lb-ft of torque in the 2014 Chevrolet Malibu and Buick Regal, with the 2.5-liter direct-injected I-4 serving as the base engine. While we'd love to see the Cruze diesel's 2.0-liter turbodiesel as an option, we think that's probably a stretch.

The roof-mounted device on this prototype looks very similar to those affixed to Google's self-driving cars shuttling around the tech giant's Northern California headquarters. We're not sure what purpose they serve on this test mule, but it could be an indication that GM is working on integrating some level of autonomous computerized vehicle control into its future models. When contacted for clarification, Buick representative Phil Colley simply stated, "We do not comment on future product speculation."