Hello
The Olympics run from 27th July to 12th August and the Paralympics running from 29th August (my birthday!) to 9th September.
Even without the Olympics your dates are still prime time summer holiday time so the chances of a sale are likely to be limited.
The number of people saying they don't want to be in London during that period and will be jetting off to foreign climes leads to images of LHR/LGW being like the last days in Saigon!
That said, never say never but it will also depend on your comfort level - booking now and being sure you have the exact flights/dates/hotels you want or leaving it until January to book and the possibility of them not being available.
And waiting could also mean that the prices go up ...
Huzzah for International Jet-setting !