If you are thinking about joining for the New Year (usually see discounts to join around then) be aware that the influx of newbies swells the ranks. It looks like it's crowded but thins out after January.
I've noticed that too. It's gotten to the point where I can see "That one won't last two weeks, that one might last a month, that one will be gone in two months..." and so on.
I once asked the manager how many of the people who sign up for an annual membership (cheaper that way) actually continue going for the year. "About half."