Windows

And as with every MS product, you have to wait until SP1 before it's worth moving over to it.

to upgrade their systems.

Microsoft as well as other hardware mfgs have continually reduced the lifespan of computer technology both hardware and software past the point of affordability.

Take cars for example, the average joe or jane consumer doesn't buy a new car every three years. The average lenght a car buyer keeps their new car is 6 years.

http://knowledge.fhwa.dot.gov/cops/hcx.nsf/discussionDisplay?Open&id=B8B5E7BE067EF33D85257544004E2071&Group=National%20Household%20Travel%20Survey&tab=DISCUSSION

We have no applications that require it, yet.

We don't need any new systems, and haven't purchased any new models in the last 12 months. No new models means no lack of XP drivers.

And, like jmgarvin said, never install an MS OS until the first SP has been out for a couple of months.

We'll test W7 within the IT department after it's release to find out if there are any incompatibilities in our 'home grown' apps. I don't expect to see it on our desktops until 4Q of 2010 at the earliest.

What's the business case, so they can manipulate their photo album without being hampered by UAC?

Low price point might be relevant for me and thee at home, with a couple of copies, justifying a 1000, plus rollout plus stuff not working.. Worse still for those who stuck with XP, as far as I'm aware the hardware requirements are pretty much as stiff as those for vista, and then there's all the old software. No way you are going to get the bean counters to sign the cheque, cost vs benefit isn't even going to start to cut it, until MS get a bit further down the
enforced obsolescence route.