Yet having the advantage that when your SQL- or other-based database fails, your nameservers don't.

I don't disagree with this. There's certainly a mode where BIND should be able to create its own b-tree by loading all of a zone and then managing it through a memory window. But there's also a more sparse mode where you just don't want to have another copy of your zone data, nor the resource consumption of having to make that copy, nor the delay between the times you pick to make that copy. Right now there's no choice since there's no zone API. One is coming, but not in 8.1.2++. -- Paul Vixie <paul@vix.com>