Coincidentally, I was just out walking along these tracks this afternoon, from Eldorado to Shingle Springs and back. The tracks are still in place west of Missouri Flat Road (Diamond Springs area, where Caldor RR was). This portion is open as a "Natural Trail" meaning it's cleared of debris & cleaned up a bit, & they made those NIMBY's take down their "no trespassing signs. The gates are in place across streets & roads, but as a pedestrian, equestrian or cyclist you have access. They are still working on the Weber Creek Bridge, to make it safe to cross. The Trail is paved from Ray Lawyer Drive south (RR west)& it looks like it will take you to the bridge--I might check it out tomorrow, but it looks too sanitized for my liking. I do like the Natural Trail part, though it was the most fun to ride a mountain bike on when it was left alone & had trees, rocks & mud flows in the way.
I thought the idea with the Folsom excursion train was to go(RR east)to Latrobe. Which they could still do; very pretty area. I'd also heard years back the goal was to bring the train from Folsom to Shingle Springs, again nice route and seems do-able if the money is there.
I'm just glad somebody is doing something with it besides building on it, which is what is slowly happening while we wait for those with visions of the Iron Horse: sadly I speak of the portion Caltrans in their wisdom took out for widening Highway 50. Maybe this scheme will happen one day, but saving the right-of-way by putting it to use will go a long way to preserving those future options.