It was quite surprising to me to discover this morning the V1.7 of GWT.
Here is the download link.
The release note says :
"(...)adds explicit support for Internet Explorer 8, Firefox 3.5, and Safari 4 as well as a few high-priority bug fixes. In all other respects, it is very similar to GWT 1.6. Note, however, that this release is version 1.7 rather than version 1.6.5 to signify a potentially breaking change for libraries that use deferred binding to specialize code based on user agent (see the next section for technical details)."