no "pinch to zoom" in Apple Mail?

Apple is so excited about multitouch gestures in the later releases of Mac OS, I wonder why they didn't include it in all of their own software applications? Like Mail, for instance. There are many times an email arrives that's too small for me to read easily. Really wish I could zoom a little to see it better. But, I can't. Apple would rather 3rd party developers come up with a hack?