A huge and important discovery. At Jingzhou's Wangjiaju Chu cemetery site 王家咀战国楚墓, 3,200 bamboo writing slips have been recovered from Tomb 798. Researchers estimate that about 700 of the slips can be restored. This tomb is 2,300 years old. The slips appear to belong to three texts: the Book of Poetry, Kongzi Yue 孔子曰. and Yue (Music) 乐. The Kongzi yue overlaps some portions of the Analects, the Book of Rites, and the Mencius. The structure of the Kongzi yue text, though, is very different from Western Han excavated manuscripts of the Analects. The portions of the Book of Poetry come from the 国风 part of the text. As for the Yue text, it consists of numbers, the Heavenly Stems, and a few simple characters. It is thought to be a musical score, but it is very hard to read. If it is a musical score, then perhaps it is a key to understanding the missing Classic of Music.
For more information, check out the Kaogu zhong de Zhongguo article here.