Adobe's update process is still HORRIBLE
Well Reader 9 may uninstall previous versions but Reader 8.20 certainly doesn't.
It might make sense with the Java JRE or some other compiler runtime ie .NET or Visual Basic (where you do indeed have cases where certain applets/applications require some older version of the runtime) but it makes NO sense with Adobe Reader - when you're trying to plug security holes!
Back in the Reader 5.x, 6.x and early 7.x days, if you had ie 6.0 and wanted to update to 6.0.4, you had to:
- Install the 6.01 update
- Reboot
- Install the 6.02 update
- Reboot
- Install the 6.03 update
- Reboot
- Install the 6.04 update
- Reboot again
Then you had to REVERSE that to uninstall!
When they finally started releasing incremental patches (the .MSP files) I rejoiced that they might have almost joined the modern era. (BUT THE PATCHES STILL WEREN'T CUMULATIVE)
But 8.20 is back to "LA LA LA LA we don't know anything about that 'other' Reader app you think you have installed... we're just pretending this is the first time you ever installed Acrobat..."
As for 9.x: I'm philosophically opposed to installing a PDF reader that doubles as a Flash thingy.
(I would probably be using 3rd-party PDF viewers if it weren't for the fact that some of the people I support have special add-ins (ie for secure PDF printing) that require the Adobe one.)