That's why I have the feeling that if they did do an intel-only rewrite, they'd keep 8.x around for legacy support, somewhat like how QT7 and QTX currently co-exist.
What is an 'intel-only' re-write? It is more about what the minimum OS X supported would be. The next step would be to drop 10.4, although I suspect they won't. You have to go out of your way to create an app that can't run on PPC, and Apple, more than anybody, knows it is dumb to write non-portable code. Just like all the PPC app programmers never intended to run on Intel, but it wasn't too hard to do it once Apple announced the change.