By now, you've probably noticed that Microsoft is releasing more and more 64-bit software even going so far as to support only 64-bit versions of some products such as Exchange 2007. We have arrived at the beginning of the end of the 32-bit era for the Windows platform. After the release of Windows Server 2008 later this year, Microsoft will deep six 32-bit server in favor of the bigger, better, faster 64-bit platform. And, after "Windows 7" hits the streets, later versions of the desktop flavors of Windows won't have a 32-bit option, either. Of course, this is a backtrack on Microsoft's part. The company had once indicated that Vista would be the end of the 32-bit desktop line, but it appears that "7" will be released in both 32-bit and 64-bit varieties, too.
In many instances, 64-bit computing is necessary and is becoming more so. Server applications today gobble up RAM for fun and even workstations themselves need more and more memory for general computing tasks. Of course, some of this is the fault of the OS itself, but that fact won't change, so IT managers everywhere will need to bite the bullet and load those systems up with RAM--and then install a 64-bit OS to take advantage of the increase in memory.
Of course, through the trickery of PAE (physical address extensions), a 32-bit server can be fooled into using much more than the traditional 4GB limit, but PAE adds a layer of compatibility complexity and can ding performance, at least ever so slightly.
To be sure, before 64-bit computing--especially on the desktop--becomes truly viable, a ton of work on both the part of Microsoft and by hardware and software developers needs to take place. If Microsoft wants people to take the 64-bit OS seriously, everything needs to simply work as well as it does under 32-bits. But even Microsoft has done a somewhat lackluster job supporting 64-bit desktop systems. Take Groove and Windows Home Server, for instance. Although Office Groove runs under 64-bit Vista, not all of Groove's features make the transition to 64-bits. And, when initially released, Microsoft's Windows Home Server product lacked a connector for 64-bit clients, leaving early adopting tech-types in a lurch. Although the first update for WHS will address this deficiency, it shouldn't have happened in the first place.
And, when it comes to third parties, I can think of a lot of problems, but one stands out clearly in my mind. We run a SonicWall 5060 firewall at work. I run 64-bit Vista at home so I can use more than 4 GB of RAM (virtual machines LOVE RAM, and I love virtual machines!). Even today, more than a year after Vista's release, SonicWall doesn't have a 64-bit capable VPN client. So, I'm forced to use a virtual machine-based 32-bit Vista client to access the network at work until SonicWall gets up to speed. I'm icking on SonicWall here, but they are just one of a whole lot of companies that look at 64-bit computing as an "add on" rather than business as usual.
On the whole, on the server side, it's still a mixed 32-bit/64-bit bag with 64-bit slowly creeping into the forefront. On the desktop side of things, 32-bit is still the order of the day but once there is a critical mass, I think we'll see the gloves come off in that space as well.
Although Microsoft has indicated some plans for jettisoning 32-bit SKUs from their portfolio, they have already back tracked on one 32-bit deadline, so we'll see what the future holds. I still think 32-bit's days are coming to a close, but it's just a matter of exactly when.