This week's book giveaway is in the OCPJP forum. We're giving away four copies of OCA/OCP Java SE 7 Programmer I & II Study Guide and have Kathy Sierra & Bert Bates on-line! See this thread for details.
Some users found it confusing to be asked to reply and then find out they had to login/register. We are working on a more subtle way to point this out. Like show the buttons differently. It will evolve as we go. The idea is to show users the functionality is there for registered users without confusing people.