I did not rely want to ask but since I don’t know

What are the differences between American PSP's and Japanese ones

Absolutely nothing except the X and O buttons are switched and there's a different region code for movies. That's it.

X - O button thing
JPN gets their updates faster
Movie Region thing

and yeah... thats about it, and there was that thing about the different screens but i forgot what the outcome of that was

thanks

edit: ow yeh btw lets say down the line I want to install a higher firmware from an American disk, would that work? or must I worry bout it causeing the firmware flash to fail

You shouldn't need to worry about using US firmware, Sony says that you need to upgrade with the firmware type of your psp though otherwise its "unsigned software" and breaks your warentee XD lol (same goes with homebrew)

oh and the bunny, you're supposed to copy the "copy the bunny into your signiture to help him achieve world domination" as well

thanks

Well the Screens are made from different brands, one is phillips and i cant remeber the other, And the japanese have been better tested for dead pixels

No it's not phillips. The Jap one is made with Sharp and the US with Samsung but I think all PSP's are now made with Samsung screens.

The original Japanese PSPs were produced in Japan, now they're all being made in China. I think the screens themselves stopped being sourced from Japan quite some time ago.