Heh, I've seen more FUD about this issue than any other
SL issue- even by extremely smart people and oldbies.
This won't effect you at all.
SLU can still be
SLU, SLExchange can remain SLEX, etc. The now TOS doesn't require you to relinquish any rights- rather it just specifies that you are not granted the right to use LL trademarks in any way except for fair use and other legal entitlements. It just puts into words what was already the case anyways. This is completely standard and isn't unusual at all.
I've seen people who have refused to log into
SL thinking that the TOS violates their right of free speech. I have seen people who think they have to use the trademark symbols anywhere and everywhere, including in forums and chat.
I've recently had my own IP right drama arising from a discussion about the ToU of my trees over at the
SL forums. The ToU was developed with friends that are very knowledgeable in IP right matters. However, some people thought that I was trying to prevent competition, or that people could be in violation for merely editing or selecting the product. Finally I had to explain extensively that the only way to violate it would be to download the sculpt or geometric data and edit it in a 3D modeler.
So please, before crying "this will take away all my rights and have the police throw me into Guananamo Bay!" please make sure you actually are interpreting what you read correctly.