Because peaking won't help much when you're looking at a poorly designed GH3 LCD anywhere outside a dark room. You want to shoot shallow DOF, then invest in a good EVF like a DP4, rather than waste time waiting for GH3 peaking...or shoot F22 with a wide angle. No-one is "happy" with AF or a blurry EVF, but I'm realistic about what you get for $1200.
I have a DP4 but the peaking function is nowhere near as good as a camera generated peaking. The DP4 only has the relatively low res output of the HDMI to find edges off. In camera peaking can work with the image data before its downsampled and so generally gives a much better result. Peaking in the form of a coloured edge is visible even if you have a blurry EVF as you can see the coloured part of the image and know that it's in focus. The high contrast peaking colour is also much easier to see even when outside. It really stands out.
Im realistic about what $1200 gets too. G6? Nex5n? Both with peaking. The Magic Lantern guys were able to add it to all the Canon DSLR's for FREE!!!!!
Dont worry, I'm not wasting any time waiting for Peaking. I shoot most days, the GH3 is just looking less and less attractive compared to what's out there now and it's only a 7month old camera.