It's no secret that application and data migration onto Windows Vista is fraught with challenges. But those of you wishing to tie the OS to http://Exchange Server 2007 need to go in with your eyes open as well. Without the right infrastructure in place, namely 64-bit, it seems that the two entities have a little trouble getting along.
But while upgrading to 64-bit on the server side may kick things up a notch in the data center, there is still the question of whether it makes sense for your http://desktop architecture. There are those who would argue that it gives you a dramatic increase in RAM, which should future-proof your network for forthcoming applications -- the key word here being "forthcoming," meaning there really is no compelling need to upgrade until those applications actually arrive.
Most people are taking their time when it comes to Vista, knowing that future hardware upgrades will eventually bring it in-house. And until the Longhorn server comes out, there are a number of key features that simply won't be available anyway, including XML-based monitoring and IPv6 compatibility.
This brings to mind the adage about people who let things happen vs. people who make things happen. The migration from XP to Vista (or Mac or Linux or fill-in-the-blank) shouldn't just be taken as a matter of course. Proactively prepping your infrastructure for whatever OS you choose should be your top priority today.