Gray's Anatomy is either going to drive you insane or delight you. This stems entirely from how appealing you find Spalding Gray - not surprising, considering the fact that the film is largely an adaptation of a one-man show. Gray's success as a performer and artist was primarily in this format, which consisted of a long monolog in the style of a story about his own life. Gray had already made two film adaptations of his work when he collaborated with Soderbergh here, but those two films (which I have yet to see) were apparently more straightforward filmed documents of his theatrical performances - essentially concert films, with an audience and no special effects.
Soderbergh chose to toss this out the window for his adaptation, keeping only the nearly iconic image of Gray sitting at his table with a microphone. Around him - both physically through the use of projections and rudimentary effects and cinematically through the use of editing - the director has placed interview subjects who had eye-related health issues (the subject of this monolog) and various embellishments like smoke, extreme lighting, and slow pans from one Gray finishing up a point to another already launching into the next segment. It's a playful and creative approach to Gray's work - one that's reminiscent of Errol Morris's documentary style, particularly in The Thin Blue Line - that doesn't abandon what works about the core material.
It's this material - both as text and in the manner in which it is delivered - that is going to be polarizing. Gray comes from a long theater background, and his performance style is often overdramatic and exaggerated - it's not a big jump to spoken-word. Similarly, his narratives are heavily neurotic and self-absorbed (although this is essentially unavoidable with a 90-minute monolog). Personally, once I had adjusted to the style, I found Gray to be absorbing and charming in the film. But it's not going to be for everyone.
As for the story itself, I don't think there are significant insights into the human condition to be found, but I did find it moving and entertaining. The process of moving from realizing he had a problem to seeking out help to coming to terms with his options and finally accepting the inevitable (risky surgery) was both interesting and somewhat enlightening, though again I'm not sure you can pull a whole lot out of it. Gray's Anatomy ended up being a fun way to spend an hour and a half.