Played up to the 10% point(according to save file) tonight on a retail review copy. Strange to play a Kirby title where you don't absorb enemies and their abilities, and thus the first world played out as the easiest platformer in existence. Finding all collectables and earning the best ranks came effortlessly in the 4-5 stages I zipped right through. Outside of the visual aesthetic and occasional transformation section(Giant tank and snowboard Kirby), it's standard platformer fare. I actually was pretty dissapointed that all the power stealing is now missing. It plays well and looks great, but the early game isn't showing any gameplay innovation beyond occasionally 'unzipping' doors.
Largest downer was the music, which is a total snorefest. The boppy and lively classic Kirby themes are nowhere in sight(from what I played) and much of the selections were so calming it saps away much of any thrill of playing this game.
Nintendo fans will eat it up and should likely have no problem earning 100% in a weekend or slightly more. For comparison, Shake It! Looks to be a zillion times more difficult to perfect.