James Blish is a great writer. Each of his books is a carefully considered meal prepared for the reader, complex, but balanced and enjoyable. His "Okie" novels are like a fusion chef's take on cowboy cuisine, full of pioneer spirit, but nuanced. His "Black Easter" is a solid meal which is made memorable by the dessert at the end of "Day of Judgement".
"Spock Must Die" (one of Blish's novels set in the Star Trek universe) reminds me of a gourmet hamburger, unabashed entertainment mixed with style and intelligence. Blish uses only the freshest ingredients (his firm grounding in philophy and science, the moral center of his characters), but he's still aiming for something tasty and accessible to the mainstream.
If you have any interest at all in Star Trek, "Spock Must Die" is a great way to encounter Blish, and if you have any familiarity with Blish, it's nice to see him having a bit of fun with the material. Highly recommended.