So good, but add some things to make it perfect.
The game is awesome man, I wish it was like Fight Night for PS2. Getting the 5X combo is really hard... I only had it once, but ofcourse only for the first round. You should add some more specials in this game. Also add some more music. Here's the main things you should add:
A time out break. So for every 5 minutes it's a break just like Fight Night and you get to have your referee heal you by pressing either arrow key.
You should add a character selection of REAL boxing players. So you can set them on light weight or heavy weight.
Add some music too, hearing just the people taunting you gets boring after a while.
Add a boxing ring and a referee make it look like if it's real boxing. Also when it's doing the life bar thing when you or the CPU is about to come up, the referee comes.
Add an audience to cheer you and boo the oponent when you or the oppoent is about to do the Special "whoopass" Move.
Add a slow motion whenever you or CPU is close to winning.
Add a training mode, so when you have a training mode, you can know what combos leads to a "Drum of whoopass!". You should add a selection of training things like a boxing bag, a CPU verser where you choose which skill is at your level.
I just hope you make another Punch out soon. 3/5.