The GCI flights are interesting. Thats another 'new domestic' route for LHR, on one hand it suggests that there is demand to/from LHR to places like Leeds, Inverness, Newquay and Guernsey. I imagine Heathrow will be pleased with these destinations as it adds to their argument that only Heathrow should be the UK hub.
Given the timings, utilisation is pretty poor, though and I don't think connections are great either? 15:45 is a bit late for the majority of US departures and 17:20 means spending most of the day at LHR if you are coming from the east coast. I image these timings might be adjusted over time, as part of the larger VS/DL/AF/KL pool, to give a quicker turnaround, if nothing else.