If you can do Outland era heroics, some of the Sunwell badge gear has lasted to 76 so far, without an upgrade. So it's not a total waste of time gearing up.

Plus its both a challenge at 70th, and training for later content. A ton of new raid encounters are like <insert fight>, except for <insert difference>.

The sunwell dailies will be quite decent gold, and there won't be a lot of competition for them either.