It seems releases with only-zeros barcodes (000000000000) display a wrong image as coverart. I first saw it on http://musicbrainz.org/release/117e2bde-923d-3f97-a0a2-aa4feb58b1b2, but it seems all releases with only-zeros barcodes are affected: http://musicbrainz.org/search?query=barcode%3A000000000000&type=release&limit=25&advanced=1