Whats up with the domains?

[Kevin]

I understand that this has been mentioned before but I think that it is 
important so I am going to bring it up again.

I have been looking at the docs on dlang and d-programming-language.org 
and was wondering which is the "preferred" website. I have seen 
dlang.org on the fourms most of the time but d-programming-language.org 
has a higher SOE ranking.  (I always find it with google)  Also, the 
searchbar at the top of dlang.org searched d-programming-language.org.

AFAIK they are mirrors of each other, would it be best to make one a 
redirect (smart, on a per-page level).  This will help things such as 
consistency in documentation, and quite importantly SEO.  For 
documentation it is important to have a domain that will be around for a 
long time, with the two domains it appears that one will drop dead 
eventually.  I think redirects increase SEO but the extra traffic will 
definitely help.  Also that search-bar that always points to 
d-programming-language.org is probably helping it's ranking.

Kevin