[FYI - similar post in the Acrobat and InDesign forums.]
We installed the CS5.5 upgrade today, and for the time being I would prefer to open my existing Illustrator docs with CS5.0, using 5.1 only when we receive v5.1 files.
I highlight an AI file, Get Info, change Open With to Illustrator CS5 and click Change All. As soon as I'm done the dropdown switches back to Illustrator CS5.1 (!!!), and nothing is actually changed in terms of what app OS X is using to open Illustrator files.
Am I missing something? Is CS5.1 overriding the system perhaps? (An older version of Freehand used to do this, which was super-annoying until they came out with a patch to fix that and about seven hundred other things.) I'm really not sure if this is an Adobe issue or an OS X issue, but I've never had trouble changing filetype associations in the past.
TIA for any tips!
OS X 10.6
Macbook Pro
PS. It's annoying enough that CS5.1 *still* can't find Pantone 485 in the Swatch Book pallete (it finds 1485 instead)... this bug has only been around for five or six versions now, I guess maybe 20 or years down the line they'll finally get around to fixing it???