Jem:
The English FA wanted to get together with their colleagues from Scotland, Northern Ireland and Wales, to select a team which was representative of the whole of the UK. However the other associations weer fearful that it might set a precedent, with FIFA ruling that the UK should only field a single national side in all international tournaments. (Northern Ireland were also far from happy at the proposal to call the team 'Great Britain' since, while Northern Ireland is in the United Kingdom, it's definitely not part of Great Britain!).
The three 'minor' associations have now indicated that they won't get involved in providing any players for the Great Britain team but, also, that they have no objections if the (English) FA fields their own team under the 'Great Britain' name. The International Olympic Committee initially rejected that proposal (as it barred some UK players from possible selection, against their 'anti-discriminatory' policies) but it looks as if it will now go ahead.
Confused? Don't worry! So is everyone else!