If you are able to read the main server webpage at
http://planeshift.fragnetics.com then you should also be able to use planeshift.fragnetics.com as the server you connect to. The server that hosts the server website is the same one that hosts Planeshift itself. If your web browser can take you to the server website it means that Planeshift will be able to connect properly to the server.
Otherwise if it doesn\'t happen that way then using the IP address would be more helpful.
As a rule of thumb, DNS changes take a maximum of 3 days to propagate across the Internet, although this can be somewhat reduced. It\'s been longer than that now so I think that if you are still facing some problems it is quite unusual.
I would also recommend against using the IP address of the Planeshift server to connect whenever possible. In the unlikely event that we move Planeshift to another server it could be slightly troublesome to coordinate people who connect using IP addresses.