How long until I see my credit score begin to go up?

I have 6 credit cards..... 3 store cards (with no balances) and 3 major cards (MC/Disc/AmEx). I plan on paying off the major cards today (MC- $4500, Disc- $5000, Am Ex-$2000). I do not have any deliquency's on my credit report....the only problem was that I was using more than 50% of available credit on each card so my score dropped a little (im at approx 700)....how long after I pay these off will I see an increase in my scores....if any?