That's a difficult and interesting question. What I like... Something that is not purely factual, dry and boring. That's hard sometimes. It's not always humor that matters, and none of the reviews have enough space to actually write erotica, but some sort of personal touch. Otherwise it's just too damn boring. Facts. The facts that aren't part of the properties or that bear repeating. If it was easy to use, intuitive, some words of advice. All the information that you "should" know before you actually spend money on something and most of the time don't.
Keep it simple on cleaning instructions and safety. A lot of the reviews are actually starting to sound the same on this.
If it's a book. I sure as hell want more than "Lot of pretty pictures or the stories were hot!" Umm, you were supposed to read it. Tell me what type of pictures. Was it well written etc.
Do I meet my own standards? Hell if I know. I've written a lot of reviews, and at a lot of different times and moods. I'm in the process of going back and editing them because I'm annoyed at how Eden added links to the older reviews. I'm improving the style or many. Initially I felt as if Eden really wanted primarily factual reviews.