Does GWT take into account the differences between browsers in how they handle Javascript and render a webpage? What about the differences between different versions of the same browser (IE 6 vs IE 7, for example)?
It does take into account the differences in various browsers but you might still have to do some tweaking on the CSS styling especially if you are using some of the newer CSS styles formats.
IE6 and IE8 are specifically recognized by GWT as different; IE7 is grouped together with IE6. (See here.) Since IE9 promises to be rather different, it will probably be recognized as a new user agent.
Hope this helps,
F.Kereki
Great fan of Open Source, Linux, and web development with GWT; all of these come together for my ESSENTIAL GWT book!