@Kylissa - I'm going to try to answer why this is so important...at least to me and many other Orthodox Christians in America.
So, I am aware that this post may offend some people, as it is a touchy subject...but it is something I truly feel is important and critical to Orthodoxy in America today.
@Kylissa and all others, please forgive me in advance if this offends you, as that truly is not my intention.
Orthodoxy is not Greek. It is not Russian. It is not Serbian, Antiochian or even American. We have Orthodox Christians that have nationalities...but our faith does not - should not - have a nationality. We can have different flavors, so to speak, of styles of hymnography, chant, etc. Byzantine, Slavic, Antiochian, and even the American arrangements of our hymnography and chants are all beautiful and good. That said...they are not and should not be the defining factors of Orthodoxy.
Our services absolutely should be in the vernacular of people. There shouldn't be a single person who has to come into the only Orthodox Church in their area and not be able to understand half the words being spoken. We shouldn't be known primarily by our food festivals. We should be known primarily by our faith and our service to others.
I LOVE Slavonic music. I just spent an hour listening to Akafist - a Russian Male Chamber choir that sings in Slavonic. It is beautiful...makes me have goosebumps at times. That said, I would if at all possible avoid having my home parish be a church that has the music primarily or even half and half in Slavonic, no matter how beautiful. I don't want to have my future children grow up needing to learn another language to be able to understand the Divine Liturgy at the church they are attending. Why? Because Orthodoxy isn't Russian! My future kids will be Americans in America that have a primary language of English. Just because the Greek, Russian, Serbian, Antiochian communities had the faith first and brought it to America doesn't mean it should be evangelized to the community in those languages.
What happened at the time of the Pentecost? The apostles were given the ability to speak the gospel in the language of the people around them. What was the mission of Sts Cyril and Methodius? They brought Orthodoxy to the people in the language they knew.
The style of the music can be Greek, Russian, or any other nationality, but the language should primarily be in the language of the vernacular no matter what country we are talking about.
How beneficial is it for us to identify ourselves as Greek, Russian, Antiochian, OCA, Serbian, etc.? We (in America) are Orthodox Christians who happen to be American.
There are more reasons it is important on an administrative and even theological level, but I have to finish unpacking before I can write about this.