The graphics are indeed updated (it's kinda hard to tell from the screenshots). They look more like the other GBA/DS Kirby games. Also the controls were switched around to be like Kirby Squeak Squad as opposed to the SNES version's controls. The game still plays basically the same.

Sound on the other hand was downgraded. It's very soft, less booming, and no more reverb.

It's a real remake, all the original games are included (and are basically the same, some treasures in the Great Cave are different but that's all). Plus there are new minigames instead of Samurai Kirby/Megaton Punch that use the touch screen, and some new unlockable adventure games. The cutscenes in the game are all CG now and you can watch them in a movie gallery.