While projects such as "The High Line" might fall outside the lines of what some folks consider to be more traditional preservation activities, I believe they are noteworthy because:

a)the organization was able to build a diverse coalition to support the project

b)they 'got the goods'-brought the deliverable home

c) not only did they borrow the concept, but other groups may ultimately
borrow the concept from them as follows:

http://www.thehighline.org/about/similarprojects.html

If none of this floats your boat, just look at the effort as a rail banking project until the day oil hits 100 bucks a barrel.

Dave