I've had a few discussions w/ my sponsor on this topic. He first came into AA in 1948 -- and after 10 yrs of relapsing, he finally got sober in 1958, and has stayed sober since. He travels extensively all over the world meeting with thousands of AA's and groups annually. He is pretty much convinced that AA is much the same as it has always been in regards to relapse rates. It works for those that do AA and it doesn't work for those that don't.
I got off on a tangent a few years back, using the statistics printed in the Big Book, regarding the rates of those "that made it." And, compared it to what I had observed locally -- and my perception at that time was: that there was a difference.
I no longer hold on to that perception. The numbers published in the book are not reliable for wide-area comparison. They were based upon a few strong groups reporting, and undoubtedly to me, those numbers were inflated, too. (Much like, when Bill wrote the title page for the Big Book -- those that were there, and Bill, later suggested that, "there wasn't actually 100 of us sober at the time -- it was more like 60.")
Here's my current thoughts on it:
1. It's not AA's job -- to get alcoholics sober and to keep them sober.

That never has been AA's job. AA's job is to 'carry the message." The message of recovery and the plan of recovery is in the book, Alcoholics Anonymous. It's the responsibility and the job -- of the alcoholic -- to use the program of recovery. "Trying to carry the message to the alcoholic that still suffers" -- is what keeps ME sober, in addition to cleaning MY house of my emotional baggage and ruins, re-creating my life -- and trusting God, as I do this.
2. Has the message changed? I don't believe the message in the Big Book has changed since 1939 -- HOWEVER the PRESENTATION of the message in the book -- HAS CHANGED.
a. The stories in the back of the book have changed. And, all together, there have been more stories printed. Many of these stories in the back of the book -- are different than the main story in the main section of the book.
b. The most potentially damaging change that I've observed is: In the 2nd Edition of the book -- someone, made a decision, to move the Dr.'s Opinion FROM page 1, of the Big Book. Thus, those that are focusing on "the first 164 pages" as their program of recovery -- are NOT using the "first 172 pages" that were the original Alcoholics Anonymous.
I believe that most all of us, who have stayed sober for a long time, have recognized the importance of "A Good First Step." Without the information in the Dr.'s Opinion -- how... are they going to take a good First Step?
The entire message of the 12 Steps and their therapeudic value & mechanism, as presented in the book -- hinges on the information in The Doctor's Opinion.
c. There is a lot of talk about "those that want to take God out of the Steps". That's nothing new. It's been around since at least 1938. And, AA's have gotten sober and stayed sober -- regardless of their "God" understandings. I know of some AA's that have stayed sober for longer than I have -- that appear to be overtly atheist or agnostic. And, many, that are overtly religious -- in their approach to God. And, many more that are middle of the road, that have stayed sober longer than I have, too.
The principles of the program are not complex. They appear to be:
a. Fully understand what your problem is. (Step 1).
b. Trust God (or Higher Power, that you understand).
c. Clean house -- make restitution for the wreckage in your life and attempt to amend it.
d. Help others. (Active in trying to help other alcoholics). Do this to the point that you recognize that there IS a fellowship of alcoholics growing up around you.... that share the same common interest of staying sober and helping other alcoholics. The easiest way, that I see to do this is: to stay connected w/ the Fellowship of Alcoholics Anonymous.
That's my take on it. I look forward to hearing and reading the observations of others!
Dallas