It was always a longer term strategy, we're still making repayments far as I understand so out new financial clout has come about because of new sponsorship deals but soon the debt will be paid off and we will be in a far healthier position, financially, than any other English club. Utd have a mountain of debt, Chelsea and City are entirely dependant on benefactors which is not where you want to be longer term.
Couple of good articles I found about it:
http://www.forbes.com/sites/bobbymcm...for-arsenal/2/
http://northlondonisred.co.uk/arsena...-inside-track/