There is a proposal / some prototyping going on for something called Platform UI Error Handling. The concept here is to be able to provide a way for the end-users to a) see what the error is b) understand what it means within their domain knowledge and c) how they can act on the error (if possible). I think this is a pretty nifty concept… An example would be say an RCP product vendor now has the ability to notify the user of an error in a polite way and possibly have a webpage launch to their support webpage with some details automatically filled in regarding the error.