I was having blu-ray playback issues using NTFS shares on WHS1 so I installed NFS using the guide like at http://www.mediasmartserver.net/2009/12/11/guide-setting-up-nfs-in-whs/ and other places.
The popcorn hour is connected to it and working great the blu-ray playback issue is gone.
My issue is that whenever I mount the NFS share from either of my Windows 7 machines it maps but the directory listing is always empty. I'm hoping someone can help with that.