red number on app store icon

It's very inconsistent. I have that number on the app store icon and for some apps it will go away while other app updates remain on the update screen although they are already installed. Is this something that will be fixed with 2.2 update or is it a problem on my side?

Page 130 iphone manual:

"Whenever you access the App Store, it checks for updates to applications you’ve
installed. By default, the App Store also automatically checks for updates every week.
The App Store icon shows the total number of application updates available. "

http://manuals.info.apple.com/enUS/iPhone_UserGuide.pdf

I think the link to the manual was a polite tip, perhaps he was too subtle.

Tap on the Apps Store icon, go to updates, the apps with updates will appear, tap on them to install them. When they are all updated the red number will go away.

Then read the manual.