Google is Problem #1, obviously. But the other one is the baroque — and unsustainable — architectural complexity of Windows 12 (which is what Vista really is). Randall Stross has an interesting piece about this in the NYT. The next version of Windows is — bizarrely — called Windows 7 by the Microsoft High Command.

Will it be a top-to-bottom rewrite? Last week, Bill Veghte, a Microsoft senior vice president, sent a letter to customers reassuring them there would be minimal changes to Windows’ essential code. “Our approach with Windows 7,” he wrote, “is to build off the same core architecture as Windows Vista so the investments you and our partners have made in Windows Vista will continue to pay off with Windows 7.”

But sticking with that same core architecture is the problem, not the solution. In April, Michael A. Silver and Neil MacDonald, analysts at Gartner, the research firm, presented a talk titled “Windows Is Collapsing.” Their argument isn’t that Windows will cease to function but that the accumulated complexity, as Microsoft tries to support 20 years of legacies, prevents timely delivery of advances. “The situation is untenable,” their joint presentation says. “Windows must change radically.”

Randall points out that the problem facing Microsoft now is analogous to that which faced Apple with its ageing OS9 system in the late 1990s. The solution was a radical break and the adoption of a completely different OS architecture — OS X. This meant a lot of pain for some die-hard Apple users, though it was partially eased by providing an OS9 emulator.

The complexity of Vista is largely a consequence of having to ensure backwards compatibility with earlier versions — which is why Bill Veghte wrote as he did. But with the power of modern Intel processors, where’s absolutely nothing to prevent Microsoft harnessing virtualisation technology to enable users to run earlier versions of Windows in virtual machines, leaving Redmond’s software designers free to design a completely new OS.