Mary-Jo and I were discussing compatibility issues around the Windows 7 kernel. The kernel being the basic (I say basic, it's one of the most advanced teams at Microsoft) brain of the operating system, needs to be at version "6.1", as opposed to "6.0" for Vista. The reason is, the "6" is picked up by applications and is recognised as "Windows Vista" and work well. If it detects "7.0", hence the name, then these applications simply will not recognise the operating system they're installing onto, and fail. Simple, but crucial.
To beat this, Windows 7 will be 6.1.****, where the asterisks are the build number. At the moment, we're looking at build 7004, demonstrated over on Scott Wylie's blog, showing off a Twitter gadget running on the desktop.
Trust me, it says "Build 7004"; uploaded in case original image gets pulled.
Although I don't have the latest copy of Windows 7 (7004), I've been playing with build 6956 which I mentioned a week or so ago. I know performance isn't stable yet, and things can change a hell of a lot in the course of 50 builds, but performance has already significantly improved.
I installed outside a virtual machine, on a dual boot laptop two fresh copies of Windows Vista (SP1) and Windows 7 (6956). As soon as it booted up, I opened the Task Manager and took a screenshot when the up-time hit 4 minutes. The results are fairly interesting:
Although I would not go as far to say that Vista is bloated or uses up far too many system resources... it does a little bit, but what really shows is how much Windows 7 has slimmed down. Let's face it, Windows 7 is basically Windows Vista with some new features, some necessaries taken out and generally stabilised quite a bit.
Windows 7, from my probably fairly inconclusive analysis, uses less physical memory, halves the amount of kernel memory being used, has a relatively stable and similar ratio between threads and handles (processor stuff), uses less processes on initial post-install, and CPU usage doesn't seem as erratic even though there are a fair number of peaks.