That's certainly a good idea, though I'd imagine that a lot of the software vendors involved wouldn't bother. I mean the betas for Vista were publicly available for over a year before its release. I ran them intermittently throughout that time and filed bugs or posted on company forums where possible, but most of the responses I got were along the lines of "we don't support beta operating systems, we'll start working on Vista support when it's released".
Vista -> 7 was a mostly painless transition aside from a few apps that stupidly have maximum version checks and refuse to install on a new OS no matter what, but then the same thing happened with Windows 8 and Server 2012. The vendors who tend to cause these problems just don't care. I have more than one vendor right now that still in 2015 insists that we disable UAC. Fortunately we've found that we can install it with UAC disabled and then immediately turn it back on, but this is the level of incompetence we're dealing with.
We're basically stuck in a never-ending cycle of stupid when it comes to specialty business software. Businesses don't upgrade because their vendors manage to do dumb shit that breaks when you upgrade things, and the vendors don't have any incentive to fix it until a lack of availability forces their customers to start upgrading.