Although it's experimental at the moment it's working. As you can see here, I'm saving a nib file from Gorm to the "Cocoa Nib" format:
Here is the same nib file after being loaded into IB on OSX:
This functionality opens up all kinds of possibilities for GNUstep. It will ease porting by allowing developers to utilize one format or to easy translate from nib->gorm and vice versa. All Mac OS X developers need to do is to make sure they save the nib files as 10.2 or later, and GNUstep will be able to read the archives.
I'm going to continue refining these enhancements until they are perfected. They're very close at the moment, but like anything new they need to be shaken out a little.
Feel free to comment. Thanks, GJC