A colleague of mine found a great article with a tip to significantly speed up the compilation time of large .Net Compact Framework projects.  I was just living it with, thinking there was nothing I could do.  I'm so glad he found that article!  It is helping speed up development of my mobile hobby projects significantly.  The slowness is due to a verification step that ensures that your application complies with its target.  Obviously during debugging, this step does not need to be executed every single time you build!  The article suggests creating a new environment variables, but I think a better approach is to use the $(ConfigurationName) variable.  When I compile for release, I want this check.  For debug, I don't.  So go read the article!  Then, if you like, take my suggestion and change the condition to...

Condition="'$(ConfigurationName)' != 'Debug'"