How Microsoft marketing "Macs" a product

The Bluetooth Notebook Mouse 5000 works "perfectly well" on a Mac as is, Ina Fried notes on Beyond Binary. But Microsoft marketers have learned their lesson. They no longer expect Mac users to pick up a package marked "Certified for Windows Vista," with a jumble of specs on the front. Here's how Microsoft renamed and repackaged the same mouse for Mac users.

It's clear that Mac users have a preference for clear, simple packaging. Now, a question: Why does Microsoft think its Windows customers are any different? " And can anyone explain why it's version 5000?