It will be available today at 9:30 a.m. Linden Time... er, Pacific Standard Time. Read and see/hear about the changes and improvements.
In the past few days, Germany and France have joined the chorus of recommendations that people move away from Internet Explorer. If you haven't, consider making the switch today.
UPDATE: If that's not enough, one day after Microsoft released a patch to a security hole in IE, another one has turned up.
UPDATE: If that's not enough, I just heard Kim Komando, of all people, say on her radio show that if you don't take any of her other security-related advice, dump Internet Explorer and switch to Firefox.