The code for the test app is open source. Although it's extremely simple compared to my game, it's meant to let me have a performance and code organization benchmark, something I can settle on and be happy with before updating my game.
The specific code that builds each chunk:
The VBO portion the chunk actually renders with:
There are some additional performance changes I want to make, mainly using indexed vertices instead since so may are duplicates, but I'm still encountering such poor performance that I'm not going to switch my game to this. However, since people tend to say VBO performance is excellent, I'm wondering what I've done wrong.