Reviews: What's Important?

I'm not a teacher, librarian, writer, editor or in any way a professional in the literary realm. My expertise is in knowing what I like.  I really try to write my reviews in a manner similar to the way I would explain or recommend a book to a friend.  Over the past few weeks I've thought a lot about why I review the way I do, and also why I review the books that I review. As a new blogger, I'm still very much developing my "voice," so I'd like some input from others on how they feel about these particular topics.

First, I have found it more useful in my reading of others' blogs to find books that are easily available in libraries or on most booksellers' shelves.  A book review, in my mind, does no good when it's not readily available. Amazon doesn't count. I don't buy books online that I haven't read, or that aren't part of a series that I know well. When I'm at a bookstore I open up the book and read a few pages to get an idea of the story. You can't do that with online books. The point being, I may miss a few books here and there, but if a book isn't accessible to my readers, what good does it do you?

Second, I'm not well versed in specific literary devices. This is something that I think I need to work a little more on. I don't know literary cycles, character development patterns or anything similar. I've found this to be a roadblock sometimes when writing a review because I'll read a book that I like, but I can't pinpoint why I like it. If I don't like a book, I'll generally know the exact reasons. But, it's harder for me to put into words the magic feeling when you just love a book.

And lastly, I'd really like to know what is important to a reader of a book review blog. Do you want a lot of plot and a little opinion? Or no plot and lots of opinion? Do you like knowing what books are similar? What is the most important thing you want to know about a book before deciding to pick it up?

Your comments are very much appreciated.