Last Sunday I tried just going for a run and failed miserably. Without the "Get Running" b*tch (as I affectionately call her! I think I've got a love-hate crush on her!) to motivate me, i stopped after only a few minutes.
So I would like to see an app that just keeps motivating me to run. It may not be all that hard either. You could choose the duration, and she could chime in every five minutes to let you know how you're going.
Maybe you could even just build that into Get Running.
Also, like others, I would like a 5to10K app.
BTW I also use Endomondo for tracking my runs and highly recommend it.