Why not?

But it still doesn't really help much. You still need a way to edit postscript files on the fly to add in commands for color or front-to-back printing. Then you still need a way to deal with network printers. And no 'native code' drivers exist for dumb inkjet printer, etc etc.

In order to do printing with 'just a browser on a kernel' your going to essentially have to recreate all the functionality provided by gnome printer dialog, samba, cups, ghostscript, gnome notification system, usb hotplug, network autodiscover protocol support, and probably half a dozen other little things. Printers are a huge PITA and I hate them and they are relatively hard thing to support.

Now granted it's certainly possible to have a browser handle all that, but it would be rather insane.

It is my fondest wish that Google would simply let a distribution handle that and do something like run 'Chrome OS' on top of a Moblin Compliant OpenSuse or Ubuntu OS.