I am going to preface this with a warning that will most certainly fail to garner me any sympathy.
I am a Mac user as well.
And I know this isn't going to help me either but it must be added.
I don't think SMB/CIFS is all that great either, it is flawed as a multivendor standard.
AFP is a vendor specific protocol that has never been largely implemented. And on the flip side SMB/CIFS is a mature understood and almost universally accepted protocol.
Mac users in my experience have a propensity in my experience to feel forgotten or abused, but what this really comes down to numbers.
Even in a perfectly fair world ~10% (The Mac market share by any guess I have ever heard) of consumer RD monies would go to Mac support, this percentage could apply to multivendor protocols (and therefore benefit everyone as a matter of synergy) or it could be used to implement a very small set of vendor specific features (and 10% of an RD budget isn't going to buy a lot of heavy lifting). I don't have numbers, but even with your perfectly fair (and unrealistic) portion, I think that the purchaseable feature set might be slim.
I don't honestly believe anyone who is seriously contemplating managing a realistic RD budget would opt for implementing vendor specific features with any sizeable portion of his (again I stress ~10%) vendor specific portion.
I also feel compelled to argue the inverse, where 90% (the non-Mac share, notable Windows and Linux) of the RD budget is going, SMB/CIFS is extremely well supported and fairly beloved. I know college professors who teach advanced Linux classes and think that SMB/CIFS is the next best thing since sliced bread.
I do not think it is unreasonable to say that Apple's SMB/CIFS support is sub par and that they could do better using Linux's open source tools. They are who I would personally petition as there you have the numbers on your side as now you are arguing for compatability with that ~90% market share. While that argument fell on deaf ears in the 1990s in Cupertino, every sign has been that they are rallying behind that logic now (where did appletalk go again?).
P.S. NFS support in the 1.08 beta, while difficult to implement in the Mac OS, runs like the devil in my personal testing. I didn't test iTunes (I don't want my library on a network attached device), but it is worth a shot.
*** Edited by Fatman because he never finishes what he starts (in this case parenthesis).