OK, a couple of my friends (domeinator, therealjoeroc) wanted to know about the whole Berenstain Bears thing so here is a summary
There is a children’s book series called The Berenstain Bears.
A lot of people remember it as being called The Berenstein Bears.
Due to the above, people are theorizing that the books actually were spelled with an E and everyone remembers it correctly, but we have somehow shifted into a parallel universe in which everything is the same but these books are spelled with an A instead.
I can’t say it’s impossible—we have no way of truly knowing unless the theory is somehow proven. However, considering how VERY malleable human memory is, there are SO MANY more plausible explanations for this effect. If you want, I could go into it, but this is probably all you need to know.