I am running on VS 2010 Pro with SP1 Beta and IIS 7.5 Express. Everything is working fine, but I am trying to access the site from another machine on our intranet and it does
IIS Express by default only supports local connections - according to a statement by ScottGu, there should be an option to explicitly enable remote connections, however.
See this blog post: Serving External traffic with WebMatrix for how to do this.