Last night, I greatly enjoyed one of their 3-hour introductory pitches for their flagship 50-hours-in-3.25-days session (called "The Forum"). The salesman/trainer was awesome -- motivated, earnest, focused, everything one could hope. I will long use some memories of his style. I noted many specifics for improving my own public voices. I met a few other interesting characters as well.
Landmark strikes me as very much a religious revival centered around many of the things that I happen to find most important right now. It's certainly not for everyone, and it's certainly dangerous for almost exactly those whom it is for.
I'm almost sure that I'll Do The Forum some time later this year. Curiosity and bravery will win out over my intellectual snobberies & the risks of choosing attitudes of openness and emotional intensity in the presence of some embedded mindviruses...
I am curious whether you closely know anyone who's done it.
Internet research suggests that there are ~1 million people who have done it -- and that tens of thousands are still fervent supporters. So I find it odd that there are only ~10 livejournal users who've listed any of the obvious find-each-other Interests ("landmark forum" e.g.) around here.