Daily Mail says 3 golds: 1900, 1908, 1912
http://www.dailymail.co.uk/sport/football/article-1038129/Its-GB-United-We-WILL-football-team-2012-Olympics--Fergies-lined-boss.html

sounds as though it's a done deed already; as for repercussions with FIFA, a United Kingdom team in the World Cup / Euros would at least stand a chance..