I’m under the impression also that Zoom Airlines which currently operates froom the UK to Canada and by all accounts overs a very good service is about to launch flights to the Eastern Seaboard of the United States flying from Gatwick, in fact they have already started recruiting cabin crew.

This would act to lower prices at least initially whilst the likes of BA and American try to do what they did to Laker Airways

But i don’t think that opening up Heathrow will make all that much difference it is congested as it is and there just isn’t going to be the slots to allow other operators in.
What i see happening is the alliances such as Star and One World will consolidate their services effectivly operating them under the alliance banner so where as currently United operate for example Chicago to Heathrow and BMI operate Heathrow to Brussels Star Allaince will consolidate the service so it would become Chicago-Heathrow-Brussels using the one aircraft.

This won’t mean cheaper prices just more profits!