Don't update unless you really need the "improvements" on the updated program. I still use XP and I haven't "upgraded" to a newer version of AutoCAD because I fear it may not work as well. I have no real need to. Everything from my version can be executed in the newer versions so anyone using newer versions will have no problems running files I send them. Same for PhotoShop, Autodesk Inventor, and other programs I use regularly. Most of the updates are just minor "enhancements" that have little effect on usability or performance so why install them? XP is an upgrade to a Vista machine because it works better. The time-line of release should have nothing to do with whether a program is considered an upgrade or not. If I installed a larger A/C unit in my home but it failed it work because it was a shitty design who in their right mind would consider that an upgrade over a previously trouble-free unit? Only people at Microsoft. The constant upgrading people do is just part of the same consumerist mentality that drives sales of complete garbage everywhere else in our society.
Why do you really need the newer upgrade of Acrobat? I don't use it and no one I send pdf. files to has ever complained. If you're at a work terminal tell your sys admin you prefer to older version and give them some BS reason about client compatibility issues if they won't listen to reason.
John Thornton