Itunes disk space reporting behavior

Hi, first time poster but I've read around on the forums. I'm using iOS 4.0.1 jailbroken with Itunes 10.1

I noticed that my apps are now taking up in the neighborhood of 6 gigs so I try to clean up apps.



This is what it is before I remove an app.

Then I decide to remove a small app thats 2.5 MB



No way it removes it removes THAT much space. So I decide to apply the changes and it goes back up to the original space. Does anyone have an idea why removing an app from the sync list causes the free space change so much?

I checked my itunes folder for the mobile applications and it's only around 2.88gb so I can't really believe apps take up 6 gigs.