This week-end I read a very nice article in the "24 heures".

The newspaper mentions that Montreux might welcome the 13th Francophonie summit in October 2010.  This event gathers every 2 years the presidents of 56 countries. It would represents 10'000 room nights in the region which would be excellent for the local economy. Moreover it would be ideal in term of image due to the number of journalists that follows the event. 
 
After that the Madagascar bid was not accepted, it seems that Montreux is the only destination left still in the run. Montreux was preferred compared to Zürich and Geneva as it is a smaller city which is more friendly.
The main issue will be for sure the security but I guess that this is easier to manage in a small city like Montreux rather than in a big capital.

If Montreux will really organize the 13th Francophonie Summit, it will be the biggest event the region ever welcomed 

Definitive answer in december 2009