M$ will continue to allow business, who do not like M$’s current products, to install XP. They would prefer that to MacOS or GNU/Linux, of course. This means that for the first time in a decade, M$ is beginning to listen to customers and might reluctantly give them what they want, an OS that works and is not bloated with unnecessary features. It also means that businesses that want more control of their software will run to GNU/Linux. What business wants to wait with baited breath for periodic stays of execution for their IT?
No, this is not about Vista, but 7, the new vapourware. Businesses do not want to buy a pig in a poke and always delay adopting a new release to they were not about to install 7 will-nilly. Customers who find they can skip Vista and 7 may skip that other OS entirely because their withdrawal symptoms subside with time. With each release they skip the cost of migration becomes more for that other OS.