Some further comments are appearing in the internet concerning this market segment and about newcomers on the ground. Turbulence in the next five years will appear, AirEnsight argues that an important number of old models being recently sold (reducing investment costs) joined with airplanes with better economics will create an interesting market movement in the coming years.
Just for adding new arguments on the discussion I tried to analyze in detail the data summarized by Leeham concerning the current demand and deliveries of each aircraft. The market is reacting similar to other segments, on which important demand is concentrated at peaks in specific years, with important cyclic behaviour (take into account 2001 and 2002 gaps in this analysis). Looks like the train is only passing by at those years, and you need to be at the station. The right move was done by Embraer capturing important demand during early 2000s, seems that Bombardier came unfourtunately late to the game. For understanding SSJ100 sales we need to consider the mayority of sales are Russian influenced contries, pick in sales early 2010s reflect this.