Windows client marketing will be led by a newly hired vice president, G. Michael Sievert. He joins the company just in time to kick off the marketing push for Windows Longhorn, which will begin at the Windows Hardware Engineering Conference (WinHEC) in Apr. 2005 and continue at the Sept. 2005 Professional Developers Conference (PDC). Sievert comes to Microsoft from AT&T Wireless, where he was chief marketing officer and an executive vice president. Sievert has also served as chief marketing officer at E-Trade and as director of brand marketing for IBM's PC business. That PC marketing experience will likely be valuable as Microsoft tries to boost consumer PC sales with Longhorn's enhanced features, such as the new graphics system, Avalon. Sievert replaces Tom Button, who has taken family medical leave.