Obviously looks are subjective so I won't try to convince anyone of anything there. I will, however, submit exhibit A for your viewing... MT did a nice job providing various pics of the 2 generations and, although the MS6 isn't represented, that's really not that big of a deal. In fact, one can easily make the argument that, with it's fugly snowflake wheels, chintzy honeycomb hideout grille and notable lack of side sills, the non-ms6 actually looked better. But again, that's debateable...
anyway...
http://www.motortrend.com/photo_gallery/112_0805_2009_mazda6_comparison_gallery/photo_01.html
Personally... how anyone can say the previous gen looks better is beyond me. It's not even close. And yes.. I've seen one in person.
Inside the margin is even larger imo. The previous gen's interior, frankly, sucked ass. Granted, it was circa 2002 so Mazda gets a pass... I guess. But compared to its competition (namely the Legacy/LGT & Jetta/Jetta GLI) it couldn't hold a candle.
So a redesign was more than in order. While its far too big for my taste... for those who actually need a backseat, I imagine the extra room is welcome. While the styling inside and out is subjective, the quality of the interior is not. Hands down, this new gen is superior to the old in this regard.
Now granted... it's a bit unfair to compare an MS6 to a new 6. However, all things being equal, I'd take the new car over the MS6 in a hearbeat. AWD is over-rated and the fwd biased version found in the MS6 is borderline pointless for most. (all it does is add extra weight and provide added security for the .001% time of the year when you may need to pull out of some snow or something) As the MS3 showed... fwd can actually be a better option. But I digress...
You all can think whatever you like but... at least try to have an open mind. Compared to its competition, (Altima, Camry, Accord, etc.) this car imo is the best looking. If it drives as well as it looks then Mazda has another winner on its hands.