As some of you will know, Heathrow is very close to several rail lines, but initially wasn't connected to any. The Piccadilly line didn't make it there until the late 70s, and the spur from the Great Western Mainline to allow trains from Paddington in 1998. The planned access from the south for trains to Waterloo (Airtrack) has a secret empty station at T5, but otherwise seems unlikely to happen Possibly more likely is a western access to the Great Western Mainline, so that trains from Reading (or perhaps even Bristol/Oxford/South Wales) could get direct access to Heathrow. This is known as the "Western Rail Link". The Network Rail consultation on the project opened today, and contains quite a lot of interesting information! Even if you don't want to respond to the consultation, it's worth a quick read to see what they're planning, and what they're not!
It is silly that passengers from the West have to go to Paddington to get to Heathrow. So this would be welcome.
Airtrack would have worked for me at my old place. Now I'm waiting for Crossrail, which will provide a slightly awkward change for HS1 at Stratford. Obviously I will move before it is open, I always do, by which time the western rail link will probably be my focus.
How well used are the RailAir coach connections from Reading and Woking? I've only ever used the Woking one. The Reading service is trying to sell separate tickets (from the rail). I would be surprised if this is cheaper.