I have a big problem opening http://localhost/ on Windows 7 (beta). I installed this os and everything went great; when I installed Wamp I saw that localhost is not working
Yea, this was a pain for me as well.
So what i did was find the "Start Wampserver", just hit the start button and type it in.
Then right click on it , select properties. I set it to run in XP servive pack 3 on the capatability tab. I also checked the box "Run this program as an administrator".
Then I right clicked the WAMPSERVER on the System Tray, and re-started all services. This worked perfect for me, hope this will help you as well.
Rob