Update 8/1/2008: Problem solved! Talked with NYC Board of Elections office yesterday morning. They had the correct ballot forwarding information in their computer records. So, in October they will forward my ballot for the presidential general election to my mom's house, and all is fine. I'm grateful to the competent and patient woman who works the phone there.

Below is the diary from before the problem was solved. Hopefully, in the future, someone doing a Kos search on a similar issue will find it useful.
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I need help! I'm about to leave for 6 months backpack traveling, and it looks like voting isn't going to be as simple as it appeared earlier. I need advice.

I'll be voting from somewhere in Central America, as a New York city/state resident.
My problem: The NY City board of elections told me I was all set to vote from abroad, and it looks like they made a mistake!
I leave for Guatemala City, Guatemala on Sunday, 8/3/2008... and just received a 'transfer notice' from my NY City address that didn't get sent to the correct address they said they would send to! I won't be staying in any place very long, and have no fixed plans for country/village - things would be much easier otherwise.

Independence Day: for us, July 4th. For Iraq, who knows?
This July 4th, like each one since the March 2003 invasion of Iraq, Republicans will wear their flag lapel pins and declare their love for our great country. Why do they love our country? To me it seems like Republicans only love it because they were born here. The founding ideas for our country are the same reasons why the Iraqi civilians are fighting US troops.  

We have a few months before July 4, 2008: Let's prepare to ask Republicans some hard and pointed questions on that day. I think we will cause them to realize their cognitive dissonance, first. Then, we can help them to understand history, and learn from it.