Question: Why is the universe the way it is?
Answer: Because if it were any other way, we wouldn't be here to observe it and pose the question.
This idea gets thrown around by a lot of people, and it just doesn't seem to make any sense. At a superficial level it kind of helps to push the question away from the forefront of the mind, maybe convince yourself that it's dealt with, but consider this:
Suppose a man were to be executed by a firing squad, all of whom were armed with live ammunition, standing relatively close, etc. Suppose that upon firing their weapons, not a single person shot the man -- all had missed. Do you think it would be reasonable for the man to say some varant of, "Well of course they all missed, I wouldn't be here to observe it were it not for their missing!"
That being said, this model is clearly an attempt to avoid that problem by positing a large number of possible universes, such that all of them are equally likely, whereas if there were only one universe then the one that exists for us to live in would seem to be quite unlikely. I expect this idea will get a lot of backing in the non-theist community.
As others have said though, the multiverse concept doesn't remove the need for an explaination for 'why is there something rather than nothing' unless the universe is cyclic, or rather, there is no start to space and time.