I know you asked for just the facts, so please forgive me for chiming with a few side thoughts. There are also some further implications you should probably consider and discuss with your boyfriend as they'll encompass your life together and with children when (and I say this as someone who married a Methodist, so I certainly understand your situation). First, one stumbling block for a couple in this situation can be the fasting regimen at home. In some cases, each spouse eats a completely different menu; in others, the non-Orthodox spouse will somewhat embrace (or at least tolerate), the fasting periods. Another issue is icons within the home, which again, is addressed in various ways. While neither of these, nor any of the others that might come up, are impediments to the marriage in and of themselves, you being Orthodox is going to affect him regardless of whether he is generally open to it, generally apathetic, or openly hostile. If you haven't at least talked about them beforehand, you may be setting yourselves up for problems even though your priest is okay with performing the marriage.
If your boyfriend received a Trinitarian baptism and can get a copy of his baptismal certificate, there shouldn't be a problem in either the OCA or GOA, AFAIK.
And I second the above post. I want you to think about what marrying someone of a different belief system will mean in the future. Typically people become more serious about their faith as they grow older, especially when children come along. Many people "re-discover" their earlier faith, while others go in a totally different direction.
What if things change - what will you do? How will the two of you handle raising children in different faiths or attending different churches? I've seen it happen quite a lot.
Personally, it was very important to me to marry someone who shared my faith (even though we weren't Orthodox at the time). It can often be very lonely and disheartening to try to live a life of faith by yourself in a marriage, as you can tell by various posts on the forum. My faith is the deepest, truest, most personal part of my being - I wouldn't want it to become a source of conflict or disagreement, or even compromise in my marriage.
Then too the Orthodox understanding of marriage as a sacrament is totally different from, for example, the Protestant understanding. A priest really opened my eyes to this truth when he told me to look at my husband: "This is the person that God has given you - to help you toward salvation. And God has given you to your husband to help him. Together your task is to help each other achieve salvation."
How can this happen if your spouse doesn't really understand or "buy into" this unique Orthodox belief?
Can people of differing beliefs have happy and successful marriages? I'm sure many could provide anecdotal evidence that it is possible. What it does require is communication and compromise - of course, those are excellent qualities necessary for any marriage!
Don't assume that "love will find a way" or that "everything will work out" because there's a better than even chance that it won't. It's better to discuss all these issues and many more thoroughly and honestly before the marriage, rather than fight about them afterward. Hopefully your premarital counseling with your priest will give you that chance.
(And finally, a personal story: in the past, my husband and I were having serious problems in our relationship, so serious that divorce was not only possible but very likely. We had counseling, of course, but at one point, during the Divine Liturgy, our priest called us up to the chalice together and communed us as a couple. That was a powerful, salvific and healing moment. Which would not have happened if we were of different faiths.)