The Windows Installer team has unleashed the beta program for Windows Installer 4.5 on Microsoft Connect. Anyone interested can sign up, provided they have a Windows Live ID tied to Microsoft Connect - there is no survey to fill out. "Windows Installer 4.5 will provide targeted features for multi-package products and advanced servicing. Windows Installer 4.5 will be delivered down level to Windows XP SP2 and above. This down level update will include the operating system independent features and fixes from the Windows Vista only release, Windows Installer 4.0." There is supposed to be a draft paper entitled "Agility Trends in Package Software" which discusses the problems the team is targeting with the Windows Installer 4.5 release but at the time of posting the link seems to be dead.