Those renderings were posted a while back and reflect a previous design. The airport has redone its master plan so many times it is hard to keep track. But as far as I know, there are no recent renderings of what the new terminal will look like but the most recent master plan can be found here:
http://www.slcairport.com/pdf/planning/SLC_ALP_Report.pdf It only shows a layout of the terminal, no renderings like posted above. While the layout is very similar as what is depicted above, there is no way in knowing exactly what it will look like and my guess is there will be at least one more revision of the master plan before construction begins. So who knows.
We all know a new terminal will happen but the question is when. The airport has been saying for years a new terminal would be built only for them to put it off for a few more years. The city hired a new airport director a couple years ago who was actually serious about putting things in motion but Rocky Anderson decided to fire him because he wanted to expand the airport and Rocky objected.
The airport currently handles about twice the number of passengers it was built for, so they will have to do it sometime. But it seems they are just seeing how long they can get away with the current terminals.