Vista SP1 is coming, and XP SP3 will be here soon too. Many people will undoubtedly be even more reluctant to upgrade to the new system as a result, and the road to widespread adoption of Vista will undoubtedly become even more difficult.
Yesterday, Microsoft publicly released the upgrade path for XP SP3 RC2, but this has placed them in an awkward position: on one hand, they need to provide better security for the large number of consumers and business users still using the XP system, while on the other hand, they need to encourage everyone to upgrade to Vista.