Not too sure where you get your info on the Abitana and Lexcom systems from.
To give you an idea of what the Abitana system can do, here is a basic rundown of what my home system consists of.
I distribute to 3 TVs a digital cable box, a freeview box and the analogue cable system we have here in Spain. The digiboxes are at my node 0, I have full ir control via the Abitana system. The telephone is also distributed to various points throughout the house via the Abitana system. My router is also conneced to the system. I also have audio distribution via the system. So any RJ45socket in the house can be either a TV, Telephone, Ethernet or Audio point. I also distribute RS232 via the system as well. All distribution boxes are in the Abitana patch panel.
"(boxes now exist for sending HDCP compatable HDMI signals over Cat5) To me this is about as future proof as you can get. Abitana, Lexcom, etc. won't do this." Wrong. This will work with the Abitana system and also the Lexcom system. Infact anything designed for a Cat5 system will work.
Also now Abitana do a High Definition Component Video + S/PDIF Audio adapter, for point to point distribution of HD.
I know that the Lexcom system can do most if not all of the above, though I'm not 100% sure about the HD (unless its a Cat5 based HD system which it can handle just like Abitana).