The ASP.NET MVC beta now supports both GAC based deployment (where you install the assembly once for the machine) as well as local \bin based deployment (where you store a copy of the assembly in the application directory). 

We will use the GAC to enable automatic-servicing updates via Windows Update (where an administrator can automatically patch a machine - like they do with the rest of the .NET Framework today, and not have to update each individual application).  One downside with GAC based deployment, though, is that it can make deploying applications that require a GAC component harder for hosted scenarios - since you typically do not have admin access on the server machine (and you need admin rights to install components in the GAC).

To make sure hosted scenarios work well (and to ensure that you don't need your hoster to install anything other that ASP.NET 3.5 in order for ASP.NET MVC to work), we will also support the ability to deploy the ASP.NET MVC framework assemblies in the \bin directory of your application.  This will allow you to just xcopy/ftp the application onto the server and have it work (no admin access or setup needs to be run on it).  The one caveat with this is that you'll be responsible for updating the assembly anytime a servicing update comes out - Windows Update can't automatically find all the application directories on a machine to-do this for you.