One thing about paper, it doesn't suffer from this problem. This on the latest Ubuntu LTS (10.04) system with up to date version of Adobe Acrobat.
Any time I try to open the downloaded August 2011 or September 2011 editions with Adobe's acroread I get:
There was an error opening this document. The file is damaged and could not be repaired.
I also tried 'Document Reader' and 'Okular' with similar results. I tried downloading the Sept edition again on the off chance it was corrupted during the download. The size of the file changed slightly, but I always got the same error?
If you are going to go completed digital, the reader technology better be rock solid. Apparently it isn't.
What's worse is this is only an intermediate step to actually get the digital copy where I really want it. On my Nook.