I Just found
this article in The Register
which talks about KeyLabs comparing Novell's NDS eDirectory vs. MS's Windows 2000 Active Directory. Here is the KeyLabs benchmark report
(requires PDF reader) and here is another link
to Novell's eDirectory Benchmark. (also, here
is what Novell says about it). I'm sure this is only round 1 and we will surely see some other reports...