If you really got into Smash Bro.s Melee you would find that the returning characters have been GREATLY modified.
Most of their moves remain the same but the amount of damage, knockback, speed, jump height, etc. are enough to make the best character from Melee the worst.
The real fun in Brawl, which is where the hype comes from, is 4 player local multiplayer, if you have yet to try that don't complain.
This is what you got in Brawl you did not get in Melee.
8 hour Single player + all returning modes.
71 ( i think) new event matches, 20 co op matches.
Co op everything
several new characters (you can't expect too many more than Melee since Melee took up pretty much every Nintendo franchise there is, nt much you can add but they managed to add quite a few.)
LOTS of new stages, plus all the great Melee stages return.
1000+ stickers
500+ trophies (compares to about 270 in Melee).
Final Smash
Several new items
stage builder
HUGE soundtrack
Online multiplayer
I honestly don't see how anyone can think this isn't a significant amount of new features and content.