I had a look at the SWPP - It seems all you need to get the fancy letters after your name is cough up some cash. I'm more interested in something like the RPS scheme, where you have to prove the standard of your work, rather than your wallet...
I don't think that's really fair m8 as they do reject more than 80% of applicants for the starter LSWPP
What they do offer though is a free mentoring to advise if your images are up to scratch for the 'L' or above, which is useful
And I do accept that their qualification is easier to attain than others
RPS ones are not a 'Pro' qualification though, and can be passed on any subject at all irrespective of your intentions for client based work. I have a pal with an LRPS who was given her title simply as she'd completed an A-level in photography - she showed her work one night, which she passed the A-level with, and frankly my kids could do better

Up to that point several of us were interested in the RPS route, and since that night none of us have bothered
Although not a member, I do attend several BIPP meetings and find they are interesting social occasions, but rarely do 'we' learn anything useful. The better evenings are when other Pros exhibit or talk about their work, as this lets you see where you stand by comparing your work to others. A year or so ago we had a presentation of truly rubbish images of kids/babies that most TPers would have been embarrassed to post, and his point was that you could make money out of pretty much anything. Oh, and he does have many 'letters' after his name too
The membership and/or letters thing is all about what you're wanting or needing by way of help, support and encouragement. For many Pros, it can be a very isolated world and the social meetings count for a lot
For my part, I like the SWPP for its generally interesting & helpful forum; and for the fact that it's given me access to a range of seminars and other helpful events I'd not have come across on my own
It also gave me the use of LSWPP as a title, which I use as a marketing tool to give me an edge over my competitors
The 'best' industry membership and qualification route is probably the MPA, but last time I looked they had a much smaller membership and didn't do meetings (at least locally to me)
Not sure if that helped at all
DD