Ummm, this might be silly, but right after my upgrade all that was on the first page of my iPad was the apple apps that come with it. I stared at it for a minute wondering what had happened to my apps. Then I swiped to bring page two into view, it was blank. Everything was there, but was on pages 3, 4, etc. I had to move them all over. I have no idea why they were rearranged, but since I needed to set up folders it was no big deal. Any chance your apps are simply on some other pages to the right of the one you are looking at?