Microsoft has released Internet Explorer 7 without the WGA validation (without the check for Genuine Windows). With this release Microsoft hopes to catch up with the popularity of FireFox.
IE 7 fixes many security issues, phishing filter, has a streamlined look and support tabbed browsing. The new release has a few minor changes like the menu bar is turned on by default.
Genuine widows user need not worry as their automatic updates will keep them upto date.
If you are using a pirated version of windows then download IE here. Choose your operating system to start the download.