I was reading the webpage of my hero, Donald Knuth inventor of T_EX, when I read his argument for “email” replacing “e-mail”. I hyphenate e-mail. Not because I think of e-mail as weird mail, but because I can't accept the idea of a letter being pronounced by its name instead of its sound, unless there's a hyphen, or it's an actual abbreviation like IRS. I don't want to change

x-ray	to	xray
q-bert	to	qbert
P-Diddy	to	Pdiddy
g-men	to	gmen
X-men	to	Xmen

etc. My wise friend Alex Boisvert noted that “ufology,” the “study of ufos” works this way, but that's why I think “ufology” sounds like a made up word. I'm all for common usage ruling — Johnson complained about using ‘fun’ as a noun — but this is just a personal choice. Everybody in the world and all my descendents can go around “emailing” each other, but I'll always accidentally read that as ‘emmail’.
As for words like asymmetric, amorphous, and amoral, the “a" isn't an abbreviation, so I'm magically okay with this.
...equal, itinerary, oblique, usurp... Oh forget about it. (But I'll still hyphenate e-mail.)

See the OED's non-committal opinion.