Have you ever met somebody who came across a certain way, then after getting to know that person better you realize that they really aren't that way? That's happened to me many times. It's true in the blogging world, too. Or maybe especially.
That's why I try to not place so much emphasis on first impression. This brings me to some tips on reading blogs. Whether we know it or not, the impression of somebody we receive from reading them has probably as much to do with how we read as it does with how that person writes. Casual conversation has the advantage of tone of voice, facial expressions and body language. Writing long, thought out pieces - such as books, articles or papers - has the advantage of putting a lot of thinking into something, as well as personal review and editing from others. Blogging is at a disadvantage because these things aren't always in the mix. It is often thinking out loud, like casual conversation, but in written form without the thought process or review. There are some shortcuts we use to convey emotion, etc., to try to fill in the gaps, but reading a blog cold and jumping to conclusions is really a hasty activity on the part of the reader.
That's why it's a good idea to read somebody's blog for a while before commenting. Or, read the history of their blog. There's a better chance of "getting" somebody's sense of humor, writing style, etc. Interact with the blogger for a while before developing an image of that person. Many people don't get these things, and it is the reason for so many internet flame wars and harsh criticisms. Reading in order to understand is a very important thing. "He who gives an answer before he hears, it is folly and shame to him." Proverbs 18:13 Read well, my friend.