For your first question

the thumbstick left and right will replace L2 and R2 and the thumbstick Up will replace pressing both at the same time.

you can download anything as much as you can with no limits , but only for 5 PS3s and 5 PSPs

i bought a poker game from psn,can i get it onto my brothers PS3 and if so,how do i do that 

have an active account there then download the game and don't delete it after you download the game, keep it

i log into the psn store on his PS3 and download it and i can do that on 5 ps3's

that is what i gathered from the instructions for movies and thanks

so it doesn't matter what ps3 you are on,seems strange they you do that but good they do

Some people here are incorrect.  You can download any item off the PS Store an unlimited number of times.  However, that item will only be functional on up to 5 activated systems. Or rather, 5 systems upon which your PSN account has been activated.  If you start running out of activations, just deactivate your account on a system you aren't using any more.  That's assumign it has PSN's DRM.  Some items, like themes, do not.

I had let four friends activate my account on their PS3s back when the Killzone 2 beta hit, so they could all share my copy.  This caused problems when my ps3 broke, and Sony sent me another one without deactivating my account on the old system.  I just called them up and got it deactivated, while also getting my friends to deactivate my account on their systems to preempt any future issues, and now I can play all my games again.

It's like Steam.  Unlimited downloads.  Which is great, because, for example, you can play any PS1 Classic you buy on either your PS3 or PSP.

I really hope Nintendo comes up with a unified, platform agnostic online network for next gen.  It's really disappointing that my VC games are locked to my specific Wii.  The ability to play games like SMB3 on the go via the DS/3DS would be awesome.