Many years ago, in the 2005 - 2010 area, it seemed like there were a lot of proposals to create commercial space habitats. These included inflatable modules, usage of spent fuel tanks, and traditional stations. At the time all presented projections of around 2020 as a construction start date. Unfortunately, due to a change of life circumstances, I stopped reading as much news as I used to and lost track of things.
I have picked back up on watching/reading the news over the past few years, but it seems like these projects have fallen off the radar and I've seen no news of progress with any of them. Have commercial space stations been abandoned as technologically unfeasible at this time, did something change in the economic or political atmosphere that delayed their implementation, or were these all pipe dreams from the start?