Nice idea, I want more jokes :)
Parodies are good, if only they doesn't repeat the same things over and over. Good job avoiding this problem :)
The graphics are nice, but although sprites doesn't need alot of care and are cheap in the matter of size, original graphics are valued better. The other grahic effects (eg. explosion) were great :). And you havn't restricted your spites to only Pokemon (I still wonder where's the granade from). Animation is clear.
I only disliked 3 things. The white frame over the pokemons in preloader, the way the preloader bar covered the trainers response (fu**) and the dialog window that got outta the screen.
The music is nice. I don't now why, but i like it ^^.
Cool style. I never thought of using a granade on other things than pokemon :D.
I must say, it was too short. You could put 1-2 more jokes in there, or try to make a longer story out of it :|.
And plz, slow down the pokemons conversation in the preloader (english is not everyones native lang. you know).
All in all, make even better things :). Next time try asking friends to put your flash on their pages to see how good they are in the field.
Good luck