From what I can understand (which I wanted to also note -- half the time I'm really not sure what GNUstep is -- correct me if my understanding of what he's trying to achieve is wrong), he's trying to make extremely portable code that will run identically in any OS right?

TideSDK has made pretty good progress on that front, by leveraging web tech. He could maybe save a heck of a lot of time by porting TideSDK to cocoa and then pushing that

There are so, so many cross-platform SDKs of various sorts. There is no particular reason to compare GNUStep to TideSDK, any more that to Qt.

If thats all it was you may as well have linked to Java Swing

so looking at this page:

http://www.gnustep.org/information/aboutGNUstep.html

I think my point still stands. He wants to bring cross-platform cocoa, partnering with an existing product might be a better way to do it

I think you're misreading the emphasis there. GNUstep is driven by an interest in objective-c/cocoa, not in making yet another cross platform framework.