It is coming.Canon does estimate the selling cost, and includes it when deciding which version to produce. They also have pro's evaluate the prototypes and see which one they prefer. While a IS version might be preferable on a consumer grade crop body, its not necessary on a FF body. The 17-55mm IS is the equivalent crop lens.
Canon wanted to see if you would buy a Non IS version for $2200 before they release a $3500 IS version.
It would have been hard to go from a $1400 version 1 to a $3500 version II IS. Much easier now that they have you prepared.
I've used mine now for thousands of shots and never missed IS at all. Only when I get to about 200-300mm does IS really become a help. I don't see any need for it on my 135mm L either.
However, if IS sells, it will happen eventually, but not soon, since Canon is not pushing out new products because of the economy. The 70D is a good body, but its not selling, people are hanging on to their pocketbook.