A therapy that's as good as a cure (such as one that is stem cell based, or otherwise) does seem likely in the next 15 years to me. I've worked on this problem briefly; my role was miniscule, but the basic idea is that you can encapsulate beta cells in an artificially immunologically privileged space, such as an alginate capsule. If done just right, this will let you sense glucose, secrete insulin, and avoid immune attack.

At any rate, yes, I think that we're getting closer to meaningful "post-insulin" therapeutics. Whether or not that will be due to stem cell biology, I don't really know; to be honest, I don't really mind what technique is used so long as it is safe, effective, and maximizes the patients' quality of life.

Here's the lab: http://www.faustmanlab.org/index.html

There's research going on for MS, another autoimmune disease, which also involves getting rid of the autoimmune cells. Here's one approach: http://en.wikipedia.org/wiki/Tovaxin

If they can get this kind of thing right, we'll live to see many autoimmune diseases cured.

Should it not be obvious that such a question exceed the ability of even the most sophisticated doctors and biologists today, not to mention anyone on HN. I'd agree that conspiracy and collusion is always part of human behavior but this doesn't prove that anyone knows the path that future efforts at cures will follow.