This is the weirdest situation I have ever seen since I'm a Mac user.
I did the standard Lion-X purchase and install. After it, with no problems, I started again the computer and took a look on the new features: mission control, launchpad, gestures and so on. But when I tried to open the iTunes, I got a screen with the message "The application stopped unexpectedly", with the options to ignore, send the report or trying again. Weird... I tried with the App Store, and I got the same error. Then I realized that most of the standard applications are not working: FaceTime, RAID Utility, Monitor of Activity, Picture Preview...
When I try to open them from the console, I always get the "Illegal instruction: 4" message. But I'm able to open them as an administrator, with heavy restrictions (for example, I can not log in the App Store while opened as an Admin). I tried to install again the iTunes, but I'm getting the same error. This indicates that something terribly wrong happened on the computer, and since I can't neither run App Store nor having a Lion CD, I'm so stucked!
This really seems to be a MAJOR failure during the update to the new OS. Is there any suggestion on how could I fix this? Attached to this message there is the error report obtained from one application (although all the different applications contain the same information)