The Impala's look hasn't become familiar over the years--it started out life that way, back in the early 2000s. And in the years since, it's grown so familiar, it's as invisible on the road as Toyota's Camry--a car that sells twice as many units each year.
The Impala's shape is penned not to offend. Not contemporary, not fresh, it's nonetheless fine to look at, not intentionally obtuse in the way some new four-doors have become. The nose faintly echoes other newer Chevrolets, and the curve of the roofline looks like the sum of the past generation of aero-smoothed sedans. Generic doesn't sell at the retail level in cars--even the Toyota Avalon is breaking the mold with its 2013 model--and to that point, the next Impala gets a lot more drama infused into its rear quarters, too. This one? It was born for the fleet, and it'll retire into one.
Likewise, the interior of the Impala hasn't changed significantly in many years, but it doesn't look quite as instantly obsolete as the exterior--at least at a few paces back. Again for 2012 GM has spruced up the look of it with new woodgrain trims and a new two-tone 'Neutral' interior combination. That's in the higher trims; in base LS trims it's drab and dull. The gauges and controls are quite clearly laid out and nothing is off-putting, but there's a utilitarian feel to the cabin that overwhelms its functional layout.