Hima Bindu Vejella has some tips on debugging Silverlight applications consuming WCF.
Source: Hima's blog
As all of us know if something went wrong in the Silverlight application that is consuming WCF, how much painful it is to investigate the problem. Debugging only help to certain level, as it do not always give the exact error message. It sucks and it eats considerable amount of time to know the problem and all that we end up in identifying nothing. If we know some smart tips in WCF +Silverlight that will help us in reducing some time and identifying the issues.