Not to be a downer, but it's pronounced "wah-GEE", with a hard G.

source: used to work a few desks down from Matt.

Wow, now there's a guy guaranteed to have his name mispronounced 99% of the time (well, at least by people who have never heard it spoken). [ edited for typo ]

I know; his brother actually just gave up and started introducing himself as "Wage" (pronounced as you'd think) rather than "WAG-ee"