One of eclipse's strength are visual capabilities. With libraries and frameworks like Zest or GMF slick visualizations and even modelling functionality can be easily realized. I chosen Eclipse RCP several years ago for one rich client project and decided against Swing ( :-() just because of these capabilities. This online presentation (it takes about 18 minutes) would surely change my mind. The visual library is Swing based, looks amazing and is free. You can download it from http://graph.netbeans.org/. I'm just thinking about combining the graph library with domain objects - should be interesting.