The 2005 National Indigenous Languages (NILS) survey lists language documentation (page 131) including literature as one of its ten indicators of language viability.
As told by Society, the weekly magazine in the Standard, however, when Prof. Ngũgĩ wa Thiong’o wrote “Murogi wa Kagogo” (or Kagooko) in Gikuyu (kik) (Kikuyu) to make a stand against linguistic neocolonialism (or perhaps cultural colonialism), scholars scoffed.
His example is important to provide a written record of endangered languages. Another effort geared toward that goal includes Basic Gikuyu classes provided at the African Language Program at Harvard University, which have reading and writing proficiency requirements. The Language Center also offers classes in Nairobi. Additionally, a textbook can be found on ERIC.
wa Thiong’o’s satire is available in both a Gikuyu version (324 pages) and an English version (more than 700). The English link provides interesting reviews at Amazon.com as well. Biographies of wa Thiong’o are available at ICWT and the Contemporary African Database. Additionally, a lamentation of wa Thing’o’s common use of English borrowings is made by Ken Kamoche at Global Beat.