GM is developing a smaller derivitive of its Theta compact SUV platform, and it's currently dubbed… wait for it… "sub-Theta". This vehicle is intended to go head-to-head with "soft-roaders" (or "cute utes") like the Toyota RAV4 and Honda CR-V. That was presumably the goal of the original Theta as well, sometime before it bloated into the Equinox, which is 22" longer and 600 lbs heavier than the RAV4. GM has dubbed these new vehicles as "sport wagons". So the Malibu Maxx is a "5 door extended sedan", but a tall two-box vehicle with AWD and waist-high center-of-gravity is a "sport wagon". Apparently, the term "SUV" is now in the GM doghouse, joining "minivan". The vehicles will be developed in conjunction with Daewoo.
(Seriously, an Equinox is not a wagon. It's just not! - John)