I got this when it came out and its still fun to this day. well it would be, but i gave it to my friend.
Anyway, the graphics have improved immensly in this new installment, mainly in the colour department, but also in the character animation. The grass moves out of your way when you ride through it, the people walk around and everything looks really swell.
The gameplay is great, theres always that extra incentive to "catch 'em all". Theres plenty of battles to do, and once you've completed the game, you can train up your pokemon by doing boss battles over and over, all the while improving your skills for when you and your friends do battle via the cable thing.
The sound is great for a gameboy game. The pokeballs make cool noises and so does pretty much everything else you come into contact with (and no...not in that way, you sick individual).
Anyway, if your a fan of the pokemon series, or just want something new to try out on you colour, you should really give this ago if you allready haven't.