This is an accounting swindle to make the figures look good. These so called profits have been from redevelopment of the old Highbury Stadium. I live in it and it's 1/3 full at most.
The whole of the north stand that faces the old pitch is completely empty because all the flats, about 70 of them, were purchased between 2 btl companies before the crunch. These companies can't get the funding now and so Arsenal have taken them to court. The companies probably want to pull out and know they will lose their deposits but Arsenal are challenging this.