Any new good game will crush The "old timers" in your group. New figs, new strategies, systems, etc.
What more importantly is after the hubbub dies down and people settle into habits, you will be swayed by what ever is the new army/rule set is launched.
We played Uncharted sea's for awhile, now its out of interest with only one (me) or two interested in playing it once in awhile.
Malifaux has many things going for it that I think will keep peoples interest and in their groups rotation for a long time to come.
The most important is the huge dedicated community that surrounds WYRD, the unique world, unique combat system, unique set of figures, and don't forget ZOMBIE HOOKERS!!