"The Angels Take Manhattan" had an AI score of 88 - the second highest this season following "Asylum of the Daleks" which scored 89.
The average AI score for the first half of the season is therefore 87.2. Season 6 had an overall average of 86.2 and the first five episodes of the Autumn half last year scored 85.6. A nice little increase in AI for Season 7 so far.
The updated Season 7 Viewing Figures chart is here: