Sorry to hear about the mets. I hope that you've been able to remain somewhat calm. I'm waiting for scan results and have had difficulty in that regard.
I currently have one met in my liver and several spots on my spine. When I was first diagnosed, I had three spots in my brain - that is where I received my targeted radiation and I gotta say that relatively speaking, it was indeed a piece of cake. The mets went away and my brain has been clear ever since.
The met in my liver has remain pretty much unchanged throughout my therapy. I haven't really had any noticable symptoms. It did make my blood chemistry 'funny' and kept me out of a clinical trial. They haven't discussed using targeted radiation for that yet. If it grows, I'm guessing that they will.
I have never been given a timeline. This disease and response to treatment varies so much person-to-person that it's all a XXX shoot. I figure that God'll keep me around as long as I'm necessary.