I read Mike's blog post at
http://blogs.msdn.com/b/jmstall/archive/2012/04/16/how-webapi-does-parameter-binding.aspx (thanks Kiran!) so I understand the rationale behind this change to use the [FromBody] attribute for parsing out parameters. However, I think this is going to have a heavy customer impact as a silent breaking change from Beta to RC. Case in point, if you have any JavaScript that uses $.post and specifies data, or if you're using the request library in node, you will just silently fail once you upgrade to RC. This is just a tracking item so that we doc this very clearly for folks who upgrade.
Updating our template to actually show some examples using $.post might be a potential idea in addition to making this breaking change well known - took me completely by surprise and there's no easy way to debug.