Yay, new game announcement!
I liked SS better than PiT, but the latter still introduced a lot of good elements I hope they implement in this game (improved sound, new gameplay gimmicks, darker story, etc.) Though, I'd like to see the return of the pseudo-free-roaming map, Bros. Attacks, Mario not looking like he's having a hangover when he's walking, and probably some other stuff I forgot. I really want them to ditch the map on the screen you're not playing on; it makes areas too linear and level-based. Then again, they could always pull it off correctly by allowing the map to scroll freely or some such...
From those screenshots alone, it looks like a sort of combination of the styles of the previous two games. Which leads me to the interesting thought...M&L1 was bright and funny, and M&L2 was more dark and serious, so...could Nintendo be planning to combine both styles in a super-wham-bam-diggity-awesome finisher to the trilogy? Or at least the game that'll make the series a trilogy if they're not going to stop here.