Plus ca change...

[Tim Bray]

I was looking up something historical and ran across the following: 

"The existence of several variants of Unix is, of course, a problem not
 only when attempting to describe the system ... but to the users and
 administrators.

 The importance of this problem is not lost upon the proprietors of the
 various versions: indeed, vigorous effort is underway to combine the
 best features of the variants into a single system."
                                       - Dennis Ritchie, 1978