dont quote me on this, but you should be able tolog into your account on the new ps3, then download all your content ect.
then get your brother to make a new SEN/PSN account. then you both should be able to use the downloaded material on both consoles. i am not to sure about both of you logging on at the same time with the same PSN account tho.
why would you want to log into the same account simultaneously on two different machines?
just make two accounts on the new ps3. one for your brother and one for you so you can log into psn and download your stuff. then your bro can use his PSN details to log in and should be able to use the games/software fine.
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