If SOM was choosen instead, I would have been afraid the tower would be ruined by design changes and the pressure to shorten the tower. With Pelli's design, I have more hope of the design being improved, and the height being increased. Also, with three proposals at the same height of 1200 feet, I think something has to change. Since the Transbay Transit Tower should be the tallest, I hope that the current height will be increased. If it is not, then Piano's towers and all other surrounding towers might need to be less than 1200, or even 1000 feet tall. Then Pelli's tower could end up being San Francisco's only supertall for the next several decades - sad for many of us here on SSP.
SOM should get a chance to design another tower in San Francisco, however I don't think their Transbay design would fit anywhere else in the city. Perhaps another twisting design with a similar exterior lattice, but on a smaller scale, on a smaller site might work?
Here is some background history and information on the Freedom Tower in New York City. As most of us know, this is another design competition that changed dramatically from the original. The surrounding shorter towers will be better designs than the tallest:
http://en.wikipedia.org/wiki/Freedom_Tower
http://en.wikipedia.org/wiki/World_Trade_Center