I am currently writing a comparison piece on Solaris - Andrei Tarkovsky vs. Steven Soderbergh and I have to admit that I was much more impressed with Tarkovsky's version.
Both films are based on the Polish writer Stanislaw Lem's sci-fi novel of the same name. Although neither truly grasp the philosophical notions explored in the book, I believe that Tarkovsky has presented a personalised adaptation of Lem's story, perhaps adhering to the notion that a mirror copy from word to image is impossible.
Conversely, Soderbergh's interpretation was very Hollywood stylized and thus lacked the metaphysical sentiments outlined in the novel. The visual elements were a bit of a cliche - dark metallics and blue 'I've seen it before' hues - while the acting is unimpressive.
But perhaps you should watch the films before making up your mind (vote Tarkovsky). At this point I am not going to include a review or plot outline as my article will address these sections, so keep tuned for a post of my article, written for the La Trobe University magazine Rabelais.