I can't help feeling that this is a missed opportunity for the regional airports - who have supported the expansion, via posters in departures or quotes in the media - http://www.chroniclelive.co.uk/g00/news/...o-12074647.

Yes, regional slots will be protected at Heathrow and will maybe grow, IF capacity at the likes of Newcastle is available - but if the whole idea of the expansion is to ensure that Heathrow, London and the UK doesn't miss out, why build it at Heathrow?
Just as en example, ministers are bleating on constantly about the Northern Powerhouse and the regional investment funds (or whatever their fancy name is these days), yet the likes of Newcastle, Manchester and Leeds/Bradford are stuck with BA feeding in to Heathrow.

Rather than have customers and staff travel to a regional airport, fly and transfer to Heathrow using a new runway, before heading off to China (or wherever else), firms will continue to invest in the south. A third runway at Heathrow doesn't make investing at Rainton Meadows any more attractive at all.
If Newcastle was allowed to expand, then surely their would be more economic benefits? Whether that is investment in infrasture or jobs and quicker, direct 'access to markets around the globe'