It's kind of fitting the same trend as
Declan and
Lachlan and
Finley and
Ronan now IMO. Spelling it
Eamonn makes it seem super-Irish.
I like the sound of it tons. I have
Eamon on my favorites list. I'm pretty sure I've come across a child named it - a nametag in a classroom, or on a roster of students. And I am certain I met a cat named it in the late nineties! So yeah, I think it's usable and happening. It's not that hard to teach people to pronounce things, if they're not too far off from what's intuitive.
- mirfak