But times have changed. Last week's preview release was an important one, to be sure, but it's going to be followed within weeks, not months, by another, equally important release. And there will be another and another and another over the next few months, with each update dropping another "feature payload" for preview testers.
What's most noteworthy about the January Technical Preview is how naggingly incomplete it is. A few of its signature features are practically placeholders. Cortana gets befuddled easily, and the new Start menu is not nearly as customizable as it needs to be. Two key apps, Mail and Music, are missing in action, and the new Photos apps is missing some key features.
But that's exactly as expected. The whole point of the Windows 10 development process is to be far more transparent than ever before, sharing work in progress and incorporating feedback into revisions quickly. It's not exactly agile development, but it's probably as close as Windows will ever get.
In the past week, I've installed Windows 10 on a dozen devices: desktops, notebooks, hybrid devices, tablets, and a virtual PC or two. I've done upgrades from Windows 7 and 8 as well as clean installs.
And for the most part it's been a positive experience. Not perfect, by any stretch, but finding rough edges and bugs is the point of putting these unfinished Windows 10 builds into 2 million or so hands.
It's certainly not time yet for a formal review, but I can share some early impressions.
The visual design is pleasing, in a low-key way.
Just about every digital product we use these days is adopting a flat design, so what was once striking about Windows 8 now seems conventional. Windows 10 has toned down some of the garish excesses of Windows 8, although the new, bright yellow and orange icons in File Explorer might still need some sandblasting.
The decision to shrink the icons on the taskbar from 32 pixels on each side to 24 pixels feels misguided; on high-resolution screens in particular, the icons are too small to be readily identifiable. At a minimum, I'd like an option to restore those too-small buttons to their previous size. An option to scale those icons would be even more welcome.
Navigation is beginning to make sense.
Good riddance to the corner-based navigation that was the hallmark of Windows 8. I am not alone in hating the original navigation paradigm of Windows 8 (move the mouse to a corner and wait for something to appear). The Hot Corners feature in OS X is similarly annoying and one of the first things I disable on a new Mac.
So the gradual emergence of the Windows 10 navigation paradigm feels right. On a conventional PC, with keyboard and mouse, you can use the familiar Alt+Tab shortcut or click the Task View button on the taskbar. Either shortcut produces a view of all running apps, allowing you to click the one you want to switch to.
It works even better on a touchscreen, where a swipe from the left, followed by a tap on a thumbnailed window, makes short work of task-switching.
The Action Center is far more functional than the Charms menu.
Give the designers of the Windows 8 user experience props for thinking outside the lines with the charms menu. Swiping from the right to display a menu is easy to get used to on a touchscreen, although making that menu appear when using a keyboard or mouse is nowhere near as easy or natural.
So Windows 10 replaces the charms with a notifications pane that occupies the same general space but has more value. The customizable buttons at the bottom of the pane actually allow you to do something with a single tap, unlike the charms, which just lead to the place where you get stuff done.
The desktop experience is profoundly better.
The single biggest complaint about Windows 8 is the jarring transition between modern apps and the desktop. Once you get to the desktop, things are familiar, but it's a constant source of irritation for people who just want to run their familiar desktop programs.
Allowing the option for modern apps to run in a window, as Windows 10 does, makes a huge difference for using them in a desktop setting. The new Start menu helps, too. In fact, the whole experience of using Windows 10 on the desktop finally feels like an evolution of Windows 7 rather than a sharp left turn.
One area that still needs work is how to allow access to settings and other app commands in modern apps. The "hamburger" menu (a stack of three horizontal lines) in the title bar feels incomplete.
Windows 10 on tablets and hybrids? Still a work in progress.
Ironically, given how much work went into building Windows 8 as a touch-first, tablet-oriented experience, Windows 10 feels most incomplete in that environment. Pendulums work that way.
With most of the desktop work out of the way, it's time for a little more attention to those touchscreen devices over the last few months of this effort.