Microsoft won't back away from a radical overhaul of Windows and is determined to kill the decades-old, decades-rich desktop, analysts agreed today.

The experts were reacting to a leak of a preliminary build of Windows "Blue," the code name for the anticipated summer upgrade to the five-month-old Windows 8. That build, which has hit file-sharing websites, includes numerous cosmetic fixes and feature improvements, all in the "Modern" user interface, or UI, the tile-based, touch-first half of Windows 8 formerly called "Metro."

By all accounts, Blue will not include any modifications to the "Classic" UI, the one that resembles Windows 7, unless Microsoft drops them into a later build.

The Modern-only changes will disappoint those who have clamored for a more Windows 7-esque desktop UI, hoped that an upgrade would restore the Start button and menu, and let users boot directly to the desktop without having to go through the Modern-style Start screen -- in other words, make Windows 8 less like Windows 8 and more like Windows 7, Part 2.

Analysts read the current composition of Blue to mean Microsoft isn't caving to that criticism, and is continuing with its strategy to emphasize the Modern UI and deemphasize the desktop.

Not that there was ever any doubt of Microsoft's commitment.

"Microsoft is serious about the Modern UI," said Patrick Moorhead, principal of Moor Insights & Strategy, of the Modern-only changes. "They're sending a signal that [Modern] is the future for Windows."

By sticking to the program, Microsoft is following through on comments it's made previously, that it's in Windows 8 -- meaning the OS's assumption that touch is critical -- for the long haul, a line it's taken since the launch of Windows 8. The latest version of Windows has not sparked PC sales as some hoped, and, based on usage patterns, has had a slower uptake than the flop that was Windows Vista.