April 8th 2014 (2014-04-08)
Windows XP - end of support - no more updates for this product - includes XP x64 Edition - last service pack for x86 was SP3 - last service pack for x64 was SP2 - ref: Microsoft Product Lifecycle Search - ref: End of Support
Office 2003 - end of support - no more updates for this product - ref: End of Support
Edit: Windows Server 2008 and Windows Server 2008 R2 no longer enter extended support on July 13th 2013, both of these products have had their mainstream phase extended to January 13th 2015. The Microsoft Product Lifecycle Search page indicated this some time ago, but only recently has it been announced/confirmed.
If I'm not mistaken Server 2008 R2 also goes into extended support the same time as Server 2008 as it isn't considered [in support terms] a full upgrade but an R2.
You are correct in that R2 versions are "minor" versions and share the lifecycle with the parent "major" product.
support.microsoft.com/.../lifePolicy (see28 & 29)
This is why searching in the Microsoft Product Lifecycle _today_ for "Windows Server 2008 R2" will show 13th July 2013 as the end of mainstream support.
However, there is also an "N+1" support policy which states that products get 2 years of mainstream support following the release of the next version of the product (or up to 5 years from the original mainstream start date, whichever is later).
support.microsoft.com/.../lifePolicy (see 1 & 21)
This indicates the date will be subject to revision as Windows Server 2012 is imminent, making mainstream support for W2K8R2 run until the back end of 2014.
Edited the post in light of the mainstream support phase being extended to July 13th 2015 for _both_ W2K8 and W2K8R2.