Not only is Microsoft working on a major revamp of its flagship Windows operating system, but significant upgrades are coming to its Office products, the Explorer browser and a range of back-end enterprise products.

"There's definitely something unique going on here," said Ted Schadler, a Forrester Research analyst.

The current status and expected delivery dates of the various upgrades vary -- and in some cases, Microsoft hasn't yet provided specifics -- but the overall effort started last year and may carry over to next year.

Unsurprisingly, the vendor is trumpeting the initiative with an intense marketing assault, and CIOs and IT directors must be ready to analyze the individual upgrades to decide which ones make sense for their companies to adopt.

"Microsoft is the strategic supplier. It's far and away the No. 1 most-used workforce technology. That makes it a critical supplier to the enterprise and every CIO needs to be extremely in touch with what Microsoft is doing," Schadler said.