@Charles: The way the WP team has been going, if they allow native support, then it won't be in the way we expect. I take the background agents as an example of this. People asked for multitasking and background applications, perhaps expecting something like we got in the wild west days of Windows Mobile. What we got is IMO, a better thought out solution to the problem.
Just allowing entire applications to be written in native code to make it easier on developers who can't be bothered to port isn't the solution. Looking at what people have been asking for, a better solution might be allowing something like highly sandboxed libraries that can be used for calculation intensive operations such as codecs or simulation. I wouldn't allow any access to data, sensors, UI or more than the most basic of APIs, only things that are explicitely passed in by the hosting application. As long as the sandbox is secure, the worse somebody can do is crash their own application...hopefully.