1up has posted a preview of Mario's latest return to block-busting, mushroom-mashing, princess-procuring platforming and the qualities observed are quite promising. Everything old is new again. Perhaps unsurprisingly, New Super Mario Bros. still plays and feels exactly the way you'd want and expect it to, even despite the addition of Mario Kart's nefarious blue shell and a mushroom that unleashes Mariozilla upon an unsuspecting world.
Actually, the preview does make it seem like becoming giant Mario makes things a tad too easy. It's an awesome sight as far as giant plumbers are concerned, but the act of running from one end of the level to the other with nothing to stop your progress seems less enticing. Hopefully that particular mushroom won't be abused in the game proper.
New Super Mario Bros. is currently slated for release on 15 March May (unless Nintendo rudely changes the date again).