Here’s what you agree to in the new Terms at the AppStore which say;
Apple and our partners and licensees may collect, use, and share precise location data, including the real-time geographic location of your Apple computer or device… For example, we may share geographic location with application providers when you opt in to their location services.
As this reads to me and has been pointed out elsewhere, you get asked to opt in when you touch location services, and you can always turn it off globally in the Location Services Setting.
Oh, and if you want to opt-out of personal information gathering in iAd?
Go to http://oo.apple.com