In less than a couple of days' work I was able to create a full featured demo app, with toolbars, menus, help pop-up's and other bits and pieces - essentially a true Rich Internet Application (RIA).
A few points that I think are worth for the novices, like me:
- if you don't know CSS, learn it fast - it is an inseparable component of GWT and enables one to do all the formatting, positioning and styling that would be virtually impossible from GWT alone;
- use Eclipse for the development / code editing - there is an excellent integration from within GWT, although, in my view, it could be better;
- it is worth considering the use of ant for all the build, deploy and run tasks - GWT applicationCreator will generate some simple scripts to do that for you, but using ant gives much greater control and flexibility to the whole process; especially if you are deploying to an instance of Tomcat that is not the one that comes packaged with GWT (which is the most likely situation in a real-life environment);
One thing I do not understand is Google's choice of their somewhat weird choice of not using Javadoc to document GWT classes - quite apart from the fact that makes it harder for us all to figure out where things are (for example, the lack of an 'All Classes' options, leaves us wandering around packages to find out a class' description), it also turns out that some methods's descriptions are missing, whilst others are actually not correct.
But those are very minor gripes - the speed at which one can craft a fully-featured RIA, even for someone who has very limited knowledge of Javascript, is a priceless feat: thanks, Google!