Hi Xeres - we were in Burkina a couple of years ago and didn't see Sindou unfortunately - have you been there? Having read your proposal I did a bit of Googling to see what we had missed! You might be interested in this site which claims it to be already "Classified by the UN as a world treasure" (scroll down about half way -
http://africatraveldestinations.net/page/4/ ) I don't know what they can be referring to - it isn't on Burkina's T List and isn't even associated with a Masterpeice of Intangible Heritage as far as I can see.
However I also came across this UNESCO report about tourism development in West Africa - page 16 refers to Sindou but the report isn't about future WHS - only tourism potential.
http://portal.unesco.org/culture/es/files/28991/11289394133AfrSynthseSept04Ang_(3).pd f/AfrSynthseSept04Ang+(3).pdfMy view? An Interesting area but whether it is "top 50 missing" material is another matter. Perhaps as a cultural landscape - but how many of these can West Africa claim with their (at least on first viewing) very similar round huts and "cult locations"? Perhaps as many as there are Christian sites in Europe/Latin America? However Burkina deserves/needs one/some WHS - we visited a 10th century archaeological site at Oursi in NE Burkina which appeared to have received a significant (or relatively so for W Africa!) amount of money and effort for a very nice little museum and a protective building which could help it fast track a nomination/inscription. See
http://www.oursi-hubeero.com/index.htm but this is also missing from Burkina's T List. The Bradt guide quotes the main archaeologist (Christoph Peltzer) as claiming it to be "One of the most important arachaeological sites in West Africa"
Perhaps Loropeni which IS on Burkina's T List remains the best hope ? Have you seen it?