Have you ever looked at the reasons that you can be banned when you signed up. There is a very long list and can be found under the related question. When a person Jailbreaks a PS3 they do so to allow the PS3 to add new functions and many of them can get you banned. You have to ask yourself why you want to jailbreak your PS3 and that new activity is often what can get you banned. You really need to read the related question and you might find that they could already ban you for things that you regularly do.
Think of it this way: if you shouldn't do it, you can get banned for it.
Boosting your score is a form of cheating and cheating can get you banned
Yes, your console can get banned if you are found cheating online.
No it will not. except when it does instead get banned because yes hacking can get you banned
No they could always have viruses or you get get your ps3 banned from going online.
Yes, it can happen, but it happens indirectly. Using the modded PSP can get the associated PSN banned, and that ban applies to anything that tries to log in to that PSN account. So an associated PS3 will find itself suspended from the PSN too if it uses that account.
You can play with a modified connection, but if you use it to cheat you may get banned from PSN. As long as you are connected to the internet with your PS3 you will be able to play muiltiplayer games. However using a modified connection to cheat could get your account on PSN banned as well as your PS3 banned so you will not be able to play online with it ever again.
Trust me dont do it your ps3 will get banned and wont work. Its not worth it trust me ive been there!
Spirit
It is not one of the reasons listed for being banned. You might want to review the related question and it's PlayStation Network link anyway.
If you get banned then you can't play.
you PS3 will get stolen, you gooch.