Heard a rumor that the ARINC HF network is to be eventually phased out in favor of satellite communications for outside US flights. Have no idea if there's anything to this. Rumors are often just that and nothing more.
I've heard that same rumor; as Tom has said, they already have a number of satellite based systems, but with a very wide customer base, I sincerely doubt that they will completly abandon their HF systems (such as their HFDL links) anytime soon. 73s Mike