Alfonso Cuaron is a great example of a director who has navigated the Hollywood system--encountering pitfalls and setbacks along the way (see "Great Expectations")-- and emerged a stronger artist. "Gravity" would not have turned out as well if the Mexican filmmaker weren't a mature and confident artist.
Yes, he had black days and anxiety and wasn't sure it would all turn out well in the end. But he honored the script --co-written by his son Jonas--and put one foot ahead of the other every day for four years, with trusted collaborators, some old, some new, at his side, and delivered the goods. "Gravity," which shared the PGA award with "12 Years a Slave," is likely to take home multiple Oscars in many tech categories as well as Best Director for Cuaron.
Will it win Big Picture? Don't trust anyone who tells you they know that answer. With the Olympics extending the Oscar voting period, many things can change between now and Oscar night, March 2.