I'm going to have to disagree with my boss about OS X. Be would not have been a better choice. Or, not necessarily a better choice.
With Be, Apple would have had the same challenges: the Classic environment, so old apps would still run; Carbon APIs, so developers have a (relatively) easy path to port their existing apps; and user interface.
I don't know that it would have taken any less time with Be OS as a foundation. I suspect not.
Where they erred is not in their choice of OS (Be or NeXT) but in decisions regarding the desktop.
Were I running the show, I would have said right from the start that a functioning Apple menu is hugely important. Etc. Etc. There are tons of great things in OS 9 that I would have retained. The break was too severe, and they're working to fix that now. The break should never have been so sharp.
(Back to my boss -- he's fond of pointing out discontinuities -- the break between OS 9 and OS X is an example. Unfortunately, I was an English major and can't follow the math. [Joking.])
I don't expect the March 24 ship date to slip. However, I do expect that OS X 1.0 will be best left to early adopters. And, come July, I would strongly recommend that Apple get off their high horse about their so-called single-OS-strategy and give people an option about which OS they want bundled with new machines.
At this point, the biggest issue facing OS X, given that it's a fact and it will ship, may be lack of software. Running Classic apps is painful. There's no good email app on OS X. There's no BBEdit, no Photoshop, no Dreamweaver, no Acrobat Reader, etc. Yet, anyway.
You might say -- well, at least you, Brent, have CodeWarrior for OS X, right? It's true, I do. Except that, with OS X Public Beta, I have to boot into OS 9 to be able to do check-outs and check-ins with our source control system. I expect that will be the case with 1.0, too. So there are all these barriers to getting work done.
Here's another little thing (I've got a huge list of them) -- there doesn't appear to be a way to extend the Finder's contextual menus. In OS 9 I'd written a few extensions which I actually use, which I rely on. (Yet another definition of a geek: one who doesn't mind breaking out a C compiler just to customize his or her desktop. OS X won't let me be a geek in that way. Correct me if I'm wrong.)