Few Help Needed to Update my PS3 JB

Hi im using PS3 Slim model 160GB . i have 3.55CFW kmeaw.. Now a days i download Games and Using Fixes/ Eboot patches to make the game work.
Im using Multiman.

I have a new doubt.

1.any new CFW comes for 4.40? its really need to upgrade to that or my cfw is fine?

2. I want to enjoy PSN games too. I have many multiplayer game. So how to use it. When ever i choose PSN. it ask to update the firmware ! :(

Please answer my questions. Thank you.