Microsoft last week unveiled Windows Messenger, which takes the simplicity of instant messaging and extends it to videoconferencing, telephony and collaboration. The technology will be available to consumers who upgrade to Windows XP, the next generation of Microsoft�s OS that will be released in October. While Windows XP offers many performance improvements over earlier consumer Windows versions, such as better memory management and improved crash resistance, those attributes are hard to sell to consumers, analysts say. In fact, in surveying the features that might attract consumers, few analysts had seen anything remarkable enough to radically drive XP sales--until Windows Messenger. "This may be the killer feature because it's the one that consumers can understand," Silver said. "Consumers can't relate to a lot of the other changes, but this is something they can see and use right away." Nevertheless, some users are already anticipating the release of Windows Messenger. Dan St. Hilaire, a Windows user and online gamer from Essex, Vt., described Windows Messenger's features as "pretty cool. It's definitely something I would like to try."