Okay, this question has come up many times (even more ever since I started that poll on ngemu.com getting opinions on an OpenGL port of Cxbx). Will Cxbx be ported to OpenGL? That's part of my plan, yes. For those of you wondering why I'd do such a thing, I'll give you an explanation as to why.
Ever since Cxbx has been released, you'll notice that it has been using Direct3D 8.0; notice a problem already? Direct3D 8 has been depreciated a long time ago and it doesn't really have any good debugging tools anymore. IMO, the driver support for Direct3D 8 isn't that great either. To top it off, PC standard Direct3D8 (and 9) does not contain all of the functionality we need to emulate the Xbox. Fortunately, OpenGL does! Using OpenGL will allow us to have a much cleaner implementation for certain functions if implemented properly. Some say that because OpenGL isn't COM oriented, an OpenGL port would be too hard. No, not really.
Ever heard of Wine? We can always use the WineD3D implementation instead. This way, we can basically have our own customized Direct3D library, and add all the custom functionality that standard Direct3D lacks... and still be using OpenGL the whole time! I've already picked up the idea and have been planning my implementation of WineD3D into Cxbx. It would be easiest to just take the needed code from WineD3D and create a custom library and call it WineX or something like that. Thank God it's GPL :)
So there you have it. An OpenGL port is planned, but as of now, it's still not a top priority. But once implemented, we can easily test it against XDK samples to ensure accuracy and speed when necessary.