Thank's for the article, good information. Does anyone have any user amounts about the different no-sql databases? Or just say two most popular ones? I guess s

Thank's for the article, good information. Does anyone have any user amounts about the different no-sql databases? Or just say two most popular ones? I guess some of them will rise above the other's in following years and some will drop. User amounts would indicate which ones have most potential to stay around and be accepted as standard no-sql databases.