But... I've read that NFS writes are much faster in NFS v3 than v2. This, of course, leads me to my question (ta-daa) :
That's news to me, unless you're referring to the ability ot NFSv3 to use larger block sizes.
He could also be referring to asynchronous writes. We *currently* don't do asynchronous writes; if a client asks us to do an async write, we do it synchronously - i.e., we log it to NVRAM - and return an indication in the reply that it was done synchronously. (We may do them asynchronously at some point.)