there is no undisputable definition for it... it all depends on each person's own view of it, hence the difference in opinions on the subject and variance in the poll.
at first thought, i'd be slightly hesitant to put it as a "true" sports car, main reason being that it is built from the platform of an econo-hatch. it's front wheel drive. it has just 4 cylinders and a pretty small displacement. it looks pretty tame, with only small exterior cues and some bigger rims setting it apart from a basic 3 hatch.
that being said, look at what it does. its suspension grips the road pretty nicely, keeps you planted in corners very well, and even has traction control and DSC to further bolster handling. the powerplant is raw, puts out 263 hp and 280 lb-ft to the crank, and throws you to the back of your seat when you get around 3k rpm and into full boost. it has enough power to require the reduction of it through the first 2 gears, and even so, you can still rip the tires, not to mention it's got enough torque stear to make your head crack the driver's side window if you're not ready for it. it's stout brakes will bring you to 0 pretty quickly and with good feel.
maybe hot rod is a better term for it. when you look at the roots of that term, its more about budget speed, not really technological prowess, even though it still lacks the generic traits of a "hot rod."
my final verdict: yes, i think it should be considered a true sports car. my car does everything that any other sports car is intended to do well, and i dont think i can deny it that classification just because it it doesnt look fast or because it can do things that other sports cars can't (like fit normal sized people in the back seat, provide room for more than one 30-pack in the trunk, lets me sit in it without my head being permanently wedged against the roof, and lets me average 26mpg in regular driving and 30 on the highway)
im sold.