“Zed” is clearly the most practical pronounciation of the last letter of the alphabet, “Zee” is easily confused with “Cee”, particularly when spelling something over the phone.
Hi there, mrrealtime, welcome to the boards.
I assume you’re talking about http://www.straightdope.com/mailbag/mzed.html ?
Fair enough- ‘zed’ is less ambiguous than ‘zee’ over the phone, between English-speakers that both know what it means, but so what? (and I’m a Brit saying this, just for the record). There are a number of other pairs of ambiguous-sounding letters/numbers - but we don’t feel compelled to change them just to make them easier to use on the phone. ‘eff’(F) and ‘ess’(S), ‘em’(M) and ‘en’(N), even ‘five’ and ‘nine’, apparently.
Fortunately, though, the Phonetic Alphabet exists (and indeed was created) to solve this very problem.
Yeah, but you can’t sing the phonetic alphabet.
Sure you can. Two eighth notes for every quarter note.
You have just given me a new aim in life.
It sort of falls down at ‘Lima, Mike, November’ (no room for ‘Oscar, Papa’ in the tune).
To me, “zed” is there purely to tell us, the Aussies (sometimes) and the Brits apart from Americans. 
And yes – on the phone, to make sure I’ve copied something down correctly, I say “Zed for Zebra”.
For my part, I spell out things like that all the time: you know, ‘“p” as in “psychiatrist,” “k” as in “knee,” “e” as in “ess,” “s” as in “sea,” “c” as in “Celt,” “g” as in “gnosis,” “w” as in “writhe,” “m” as in “mnemonic.”’
RR
Zed’s dead, baby. Zed’s dead. 
Not to forget “H” as in “Preparation.”
I can’t remember ever singing the Alphabet Song as “X, Y, Zee”, it was always “X, Y, Zed”. It never bothered me that it didn’t rhyme that way - that was just the way it was (I was an uncritical kid at that age ).
I thought it was P as in bath (the P is silent in bath).
Yeah, and I’ll bet you pronounce it ZEH-bra instead of ZEE-bra, too.
Pee in the bath is completely unsanitary, Mangetout, and you know that every bath contract has an unsanitary clause.
Well, that’s what the nice Mr Attenborough taught us
That may be so, but any child will tell you it is indeed silent. Unless you do it standing up.
Lifeguard: “I’m kicking you out for peeing in the pool.”
Mangetout: “But why just me? Everybody pees in the pool!”
Lifeguard: “Yeah, but not from the diving board!”
Actually it’s to help us Americans spot those sneaky Canadians in our midst.
You can’t fool me. There’s no such thing as unsanitary clause.
And while we’re at it, is it Lima (lye’-ma) as in beans, or Lima (lee’-ma) as in Peru?