I have not seen any of Ocean Preludes. Being a film buff I am not sure why I missed those but anyway. I went to the movie primarily because it has George Clooney and it is directed by Steve Soderbergh(Erin Brockovich, Traffic fame).
I liked the plot, the characters, the team work. The movie is long but manages to glue you to your seat. The plot is very well executed through good acting, super editing, and excellent screenplay.
Whenever such movies are made the challenge of the director is to make people realize that all that is being shown can actually occur. There has to be a element of reality in the sense that the plot should not look like a fiction. Steven manages to do just that. This reminds me of a similar challenge which the director of National Treasure James Turteltaub faced while making us believe that the entire Treasure plot is actually true.
The same happens to you when you see 13, it feels real. The director also manages to give every actor enough screen presence so that they leave a mark. This is again difficult considering the huge star cast. Every member of 13 has a role to play and they do it well. I loved to hate Al Pacino. He manages to be the mean guy very well. George Clooney and Brad Pitt are excellent too.
All in all, a very good movie. I would recommend a definite watch. It is a great effort by the director and such cinema should be encouraged.