Jim Allchin has started his farewell and Vista promotional tour, and we have videos. Allchin, Microsoft co-president of the platform, products and services division, is planning to retire at the end of this year (when Vista ships) after 16 years in the Redmond trenches. News.com readers came up with the questions for Allchin, and he explain why he thinks users will want to upgrade to Vista. The overriding reasons, he said, will be safety and security. He also responded to a question comparing Vista to the Mac. The new WinFX APIs might generate new enterprise applications and mobile features will appeal to enterprise users. Allchin also addresses the requirements for running Windows--the more memory the better and fast graphics cards for the 'glass' effect, but no specifics yet. He also addresses the question of who will run the Windows platform team after he leaves.