In reply to Robnolan:
In the past, I've used clubs a lot, as a way to meet people to climb with and to share lifts, going on meets every month. Now, I have regular climbing partners, but am also a member of a club and do try to go on some meets, but life is busy and it's often easier to just go climbing with a regular partner for the day.
The great thing about clubs is the chance to meet more climbers locally, the chance to share lifts, the opportunities to use huts (both the clubs and also other clubs'huts). You usually get 3rd party insurance and membership of the BMC as well as part of your membership. You can also often get discounts off gear.
The bad things are that some local clubs can end up not being very active climbing wise, and that you sometimes get some people who think that they are like your boss at work and who start trying to tell you what to do! Also, you do sometimes get the odd person who you would rather avoid, and sometimes a club makes it harder to do this!
I also personally am not at all keen on clubs that move too far away from climbing, into social activities or walking/mountain biking etc. I like the focus to be on climbing.
I've met some very good friends, had some magnificent holidays and weekends through clubs and continue to enjoy them as an easy way to have a weekend away as part of a mixed group of people.
Keeping a club going is about incentivising and encouraging experienced members as well as attracting new ones - it's all about balance.
I think it's also important to make it easy for people to pay any subs. I've been a member of clubs and been willing to remain a member, but paying subs meant going to an obscure pub on a week night in another county, no one could tell me how much the subs were, so it just became impossible to remain a member! (they did suggest I send them a blank cheque, but I wasn't too keen on this idea!).