Sony confirmed in a press release, as well as in emails to PSN users, that the PSN name will be no more. The PSN will be changing into the SEN (Sony Entertainment Network). The email assures us that this is “a change in name only.” Your username and password will remain the same, and anything you purchased for your PSN account will now belong to your SEN account.

Full article:

http://www.ps3blog.net/2012/02/06/psn-is-changing-to-the-sen-this-tuesday/

I cant help but thinking that there must be some obscure juridic reason
for this change or just for people to forget that once the psn have been hacked to death. So it's like a fresh start for Sony. Anyway, i still keep my
PS3 and will still use the SEN network...

I really do not see what difference it will make