Smallish hatch/wagon, similar in size to a V40, maybe up to a V60, with a Volvo-ish front-end (squared off). BUT the rear window wrapped around to hide the d-pillars, similar in style to the rear glass of the CT200h or a Suzuki SX4.
I saw it at a distance and in profile only, my eyes could have been playing tricks on me but it looked sharp and I didn't recognize it. Now it's bugging me.
I thought some images might help.
CT200h
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Suzuki SX4
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Sorry, I thought we were just posting wagon pictures.
The Saab 9-5 SportCombi did have that wrap around rear glass, but otherwise it doesn't really look like my mental picture. Def. a wagon and not an SUV or a Mazda5 (one of those is in my driveway).
I'm wondering if it was a Lancer Sportback and my brain interpreted wrap around glass in that empty area under the spoiler:
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It's definitely got the squared off front end I saw.