Be aware that because XP doesn't have an up to date SSL implementation (the part of the system that makes the padlock icon in your browser work on secure pages) it'll increasingly struggle to connect to many websites.
More and more sites are using SSL, and where they handle payments they're required by the banks to only support current secure implementations, while the older protocols supported in XP have known weakness and can't be supported.
I loved XP too and still use it selectively on a standalone, non-internet media centre PC, but over coming months your mileage for internet use will drop off fast, it just won't be able to connect to half the servers out there.
Win7 is good, agreed. Win 8 kind of sucks, haven't tried 10 yet, but good to see it's free to win 7 and 8 users.
Andy