All user accounts now must be tied to a material world identity. When you log in for the first time to the new TOS, you have agreed that you have provided (or will update before the deadline) your account information to provide them with your material world identity if you haven't already done so. The new TOS does not go into effect until the end of April and you have 30 days from that time to complete your updates. If by then you do not have your material world identifying information on file, then you are no longer eligible to use Second Life and they can take all your stuff, including your intellectual property rights to all of the content you've created.
This could have very wide sweeping implications for the culture of Second Life. Back in the day (around 2005 or so) when one first registered their information was put into a publicly accessible database. Pretty much anyone who didn't want their private information hung out on a shingle for the whole world to see used assumed names and other created information. Hopefully the database that holds everyone's identifying information is no longer accessible to those who might want to harvest said information.
Certainly the marketing value of your personally identifying information in relation to your Second Life purchasing habits (all neatly tracked now through Xstreet and the SL transaction history) must be astronomical in material world monetary value. Should Linden Lab decide to sell this data to marketing professionals, it could be very profitable to them.
I have to add too, that I've been surprised to see so little being said about the new TOS. Maybe everyone is too busy playing with the new 2.0 viewer. Hmm?