I recently bought a new MacBook Pro and used the iWork '09 trial that was offered - and thought it was great. I made lots of new documents in the trial period but at the end of it, I thought I would see if I could install my old version of iWork 08 from a previous computer. I found that I could do this, but it would not open any iWork '09 files, so I had to buy iwork '09 anyway as I had done so much work with it. I got caught out I think! Did anyone else find this too?