I love them, and have several pairs in different styles and colours. They are my main footwear for work. I like the Gizeh (toe post) style best, but also have Arizona and Madrid, plus a couple of pairs of footbed sandals from Next, which I also find very comfy - although the footbed is not as highly profiled as the Birkenstock one. Personally, I've never had to break mine in, but they do soften up and get even more comfy after a few wears. My only problem with them is that they usually end up stinking long before they wear out, and I end up chucking them away because of that.
I'm nearly the same as you Pick-a-Lily, clogs, 2 strap, Madrids, couldn't wear any other type of shoe now, they are so comfortable. I started out with Gizeh about 7 years ago and hated them, left them in a cupbard for a year and the next summer tried again, they were amazing, I'd obviously broken them in properly after time. I have difficulty finding any shoe that fits me, I'm big foot incarnate when it comes to my feet, I'm a 41 regular -no size Clarkes will fit my feet but I can wear my Birkis with no pain whatsever, whereas before discovering Birtkenstock, fond it very difficult to to go far without extreme foot pain and that was with hush puppies and other good quality shoe.
I've seen more and more people wearing them, especially in the last week, at my opticians, lady said she couldn't wear any other shoe for work as they are so perfect. Loads of mums at school, Madrids everywhere, proper Birkis as well, not copies, I think people are realising that the orginals are the best. And generally out and about, so many women wearing them.
My hubby has a pair of shoes (no they weren't cheap @ £56 but that was in a sale, normally £98) and he wears them to work everyday and has been for nearly 5 years and walks a hell of alot in his job. I buy new insoles every now and then and the soles are still perfect and his feet don't sweat either.
I do know some people just don't get on with them at all and I feel that shows how different we can be.