GWT 1.7 is out, if you work with the google plugin for eclipse you can just upgrade it from “Help<Software Updates”. If not you can download it from http://code.google.com/webtoolkit/download.html.
This patch does not have a lot of changes, just some bug fixes and support for Explorer 8, Firefox 3.5 and Safari 4.
Posted by jellebeuselinck 
GWT blog 