Customers hoping to buy desktop computers with Windows XP installed can’t find them at Office Depot. One alternative is to purchase a computer with Windows Vista Business or Ultimate installed and use the enclosed "downgrade" certificate to retrofit Windows XP Pro. Important: Vista Home Basic and Home Premium editions do not qualify for the "downgrade" to XP certificate. Before buying, make certain that the computer does indeed include a "downgrade" certificate.
Read June 4th article: Microsoft’s [CEO Steve] Ballmer Touts Vista-To-XP Downgrade Program Translation: "Our newest product has problems, but if you’ll buy its highest priced versions, we’ll allow you to use our older, faster, more reliable product."