According to tech site Neowin, but yet to be officialy confirmed by Microsoft, the third Service Pack of Windows XP will show up around April, 29th, 2008 on the major consumer download areas of Microsoft (Microsoft Update, Windows Update, and Download Center).
Based on the last test build the SP3 will weight more than 300MB. As usual for any Service Pack, the SP3 will be cumulative, meaning it is possible to install just SP3 on a any clean install of XP.
Between the new features there will be the Network Access Protection (NAP), while Internet Explorer 7 is still kept as separated download.
Neowin – Windows XP SP3 Release Dates: http://www.neowin.net/news/main/08/04/15/windows-xp-sp3-release-dates
Microsoft Windows XP Service Pack 3 Overview: http://www.microsoft.com/downloads/details.aspx?FamilyID=68c48dad-bc34-40be-8d85-6bb4f56f5110&displaylang=en
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