6,000 more NATO Troops...can someone help me with math?

(I remember now, in my bleary-eyed Saturday morning state, that much of this was already posted by Greyhawk in The Mudville Gazette)

President Obama laid out two rather startling goals during his speech on Tuesday night. The first was his claim to "begin withdrawing" troops by July 2011. But even more incredible than that was his claim that NATO would send an additional 6,000 troops (some sources say 7,000 or even 10,000!) to ISAF's contingent in Afghanistan.

I need to do a little math.

To be certain, a number of countries have pledged more support. Britain is expected to offer an additional 500 troops, to join their existing contingent in southern Afghanistan. Italy has just offered 1,000 troops (H/T Courtney Me109), which may grow to 1,500 troops. Georgia, Poland and Slovakia have also pledged more troops to support ISAF's efforts. Indeed, according to NATO's Secretary-General, "over 25 countries" will send additional troops.

Who? And most importantly, do the additional troops from these countries compensate for the countries which are already leaving?

The nations which have proven themselves to be the most adept at fighting counterinsurgency in Afghanistan have begun to leave ISAF's contingent. Australia has said no to more troops, for the time being. The Danes are cautious about sending more troops, as well. The Canadians and the Dutch are removing 5,000 troops from Afghanistan in the next few years.

The German and French have said "nein" and "non" to more troops, respectively.

As Greyhawk asks, can someone help me with the math on this?