>Apple has chosen it, and I looked at webcore, and its great for Mac OS X, I think I'd start with the AtheOS port, rather than apples.
I'm not so sure. a) the AtheOS/syllable port is an older port b) I haven't heard about AtheOS before you mentioned it but after looking at its web page, it appears to be a Linux clone with a lot of Linux stuff already ported, including a minimal qt. Since qt is the gadget toolkit used by khtml, the AtheOS khtml port might still be based on that (just a guess) which would have made porting significantly easier. Apple, on the other hand, already has done the untie-khtml-from-qt-and-linux job. One would basically be following their tracks, look at the changes they made, and substitute Amiga APIs. Apple's changes are commented in the source code.