HOMEPAGE for media-libs/opencv should be changed to: http://opencvlibrary.sourceforge.net/ or http://opencv.willowgarage.com/wiki/ (where the former redirects to).
Thanks for reporting this change, assigning to maintainers.
+ 27 Dec 2008; Thomas Anderson <gentoofan23@gentoo.org> metadata.xml, + opencv-1.0.0-r1.ebuild: + Fix homepage, bug #252367 by Thomas Pani. Tweak metadata.xml a bit + Thanks for the report!