Well, if one of two co-creators of the game leaves then it probably means time to backup everything possible. Screenshot your stats, shop items, forum threads, save map xml codes (including your favorite ones from other makers), copy your friendlist, if you care about your friends stats then save their cheeseformice profile pages. The game obviously lives its last days right now and I hope Tigrounette is going to publicly upload source code of the client and the server after shutting down.
Ten years is a very optimistic presumption, my bet is an year or two. If you do care about the game and its community, no joke, it's time to backup everything important to you and ask your in-game friends for contacts.
All staff members left in the past recent years and now the very person who gave this game its soul and charme is leaving. Meli was the face of the game, I don't see how this project is going to stay alive without her. The other guy got lucky for having her in the crew, sometimes just having a game with a f'ed up hitbox bug that allows to jump from a wall is not enough for an infinite money milking...