On the other hand, your other post says you fly in to Gatwick, London's other airport.

That's a very good question. If the travel agent knew we were flying into Gatwick, why would she look up train fares from Heathrow? I'm going to corner her on that. Thanks for pointing it out.

You can alternatively get from Heathrow to the centre more cheaply on Tube alone, but it's a much longer, noisier journey (60 minutes not 15).

Thanks for pointing this out. I think a short ride to the hotel is much preferred.

Thanks, also, for the link to TheTube.com. I anticipate we're going to be using it to get around while we're in London.