Several "insiders" have already enquired about choice of, and access to, hotels etc in and around London during this period. I thought that it might help if I summarised the main clusters of sporting activity, indicated their locations and suggested 1/2 Marriotts that they might like to consider.
1.Olympic Park, Stratford, East London.
Most athletics (ex the Marathon),cycling (track), handball, hockey,swimming, diving, waterpolo, basketball
Hotels: London - Ren St Pancras, M West India Quay; near London - Ms Hanbury Manor, Tudor Park, Waltham Abbey, Cheshunt
2. East London, approx 5/8 miles from Olympic Park.
Excel Arena: boxing,fencing, judo, table tennis weightlifting, wrestling
Greenwich Park: equestrian dressage, eventing, jumping, some pentathlon
North Greenwich arena: gymnastics (artistic and trampoline)
Lee Valley White Water centre: canoe slalom
Hotels: as for 1 above
3. West End (i.e.centre) of London.
Hyde Park: Swimming marathon, triathlon.
The Mall: Athletics marathon and road walk, cycling (road).
Horse Guards Parade: Beach volleyball
Royal Artillery Barracks: shooting
Earl's Court: Volleyball
Hotels: JW Marriott and Marriott, Park Lane, M Grosvenor Sq, County Hall and Marble Arch
4. North-West and West London and Thamas Valley
Wembley Arena: Badminton, football
Hampton Court Palace: Cycling (road)
Eton Dorney, Buckinghamshire: rowing and canoe sprint
Hotels: M Twickenham and various Ms etc around Reading
Weymouth/Portland, Dorset: Sailing
Coventry, Glasgow, Cardiff, Manchester, Newcastle: Football
I hope this list and the related "hints" are of some help. Please note though that I have not tried to present an exhaustive list of all events.