XP SP2 is suppose to change XP pretty heavily. Microsoft is describing it as XP Reloaded. It is suppose to be packed with security enhancements and change a lot of the service, firewall, and security defaults. Some of the new security features will include network protection, memory protection, safer emailing, more secure browsing, and improved computer maintenance.
In its testing (from what I have read) XP SP2 will change a lot of the system defauls wich may cause problems with some applications.
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