did you find solution because i have same problem
I tried to update one app (over 20MB) in iPhone 4, but it get display in waiting/loading state. I tried the following option to delete.
1. Sign out/Sign in option
2. Connect with computer and delete that app from iTunes and download and then again install, but it display two same apps, one with waiting/loading status and other is installed in iTunes on iPhone( when connected with computer) but in iPhone (not connected with computer) it display only one app with loading/waiting state.
3. Rebooted iPhone.
4.Cannot delete them as the little red 'x' doesn't appear when waiting app.
Still I am unable to delete this waiting app from iPhone.