We have mathoverflow.com with 144000 questions and answers, and we have math.stackexchange.com with 522000 questions and answers. Isn't there a redundancy? Shouldn't both sites be merged? I propose a merge into stackexchange, because it's larger and it's the main domain of tens of other subdomains.
update
The downvotes show that you disagree, and David explained the difference between the two sites. But that difference isn't obvious from names like "mathoverflow" and "math.stackexchange", as my asking shows. Shouldn't the difference in target audience be made more clear then?