>When I create a new WPF project, VS creates it targeting the .NET Framework 4 Client Profile, instead of .NET Framework 4.
>
>Anyone know why?

(a) Because those DLLs are all that you would normally need at runtime - for WPF or WinForms apps (most of the stuff that is excluded is ASP.NET related)
(b) The Client Profile is part of Windows update so in many cases will already be installed on target machines.

>Can I change the default that it gets set to for new projects?

Unless you actually find that some functionality that you need is missing I'd leave well alone. If you really must then, AFAIK, the only way to change the default option is to hack the WPFApplication.csproj template.....