ASP.NET MVC 3 RTM
Yesterday Microsoft released the RTM version of ASP.NET MVC 3. We've added the relevant DLL's to the Global Assembly Caches of all AppHarbor web servers. This change may break apps using beta and release client builds of MVC 3 running on AppHarbor. If you find that you app is not working, please upgrade to MVC 3 RTM, fix any breakage and push to AppHarbor.
The breakage is due to Microsoft using the same DLL version number for both release client builds and RTM-builds of MVC 3. Thus, even though your app references a local lib-folder release client MVC 3 DLL, once we add the RTM dll to the GAC, your app will start using the GAC'ed one. There's no way to override that behaviour, unfortunately.
We add MVC dlls to the web server Global Assembly Caches to give developers coming on to the platform the best experience possible. ASP.NET MVC installs itself in the GAC on your local machine and we want to make sure that our platform is compatible with that configuration.
We are currently working with Microsoft to ensure that this will not be a problem with future versions of ASP.NET MVC.