Alas, as others have said the flash just played far too slowly and messed up the syncing (though that may be the fault of my computer?). So i watched it on youtube.
The animation itself was very slick, the voice acting decent, and the music great too. I think your humour is slightly off and a bit slow. It doesn't really flow. I enjoyed the Pikachu joke but it was a bit drawn out before the punchline. There was no explanation as to why Charmander wouldn't obey Ash. The "she was diggin' it" quote was funny too!
So, battle commences - Pika's lazing off and doing his thing - charmander comes out and uses growl, but misses. Then maybe capitalise on how the heck growl (a sound) can miss a target!!! And then maybe have your badass squirtle come bop dugtrio on the head. Your animation looks superb and sounds superb, next just try work on the flow so it feels more natural. Good work!