Sober Thal said:
Yes, to a point.
Not so far as to call them 'an idiot and completely ignore anything they have to say, no matter how valid or thoughtful it may be.'
I think that is a bit harsh.
I think that this is about right.
On the one hand, I won't completely and utterly dismiss someone who doesn't employ high-level of spelling/writing/vocabulary skills (especially on the internet).
On the other hand, there is a direct relationship between how well something is written and the time and attention I give it when reading it. I believe that's there's nothing wrong with this.
After all, in the world of spoken communication, let's say you have 1) a well-spoken person who expresses their ideas clearly and 2) a person who constantly uses slang and vernacular and doesn't necessarily express their ideas clearly.
Most of the time, especially if you're wanting to discuss a subject intelligently, you'd much rather talk with person #1. On the other hand, if it's just a casual conversation, you may want to talk with person #2, especially if their slang and vernacular is the same as your own.
I realize that I picked two polar opposites for my example, but you see my point. In the end, whether it's spoken or written, proper language expression IS important. Just how important it is varies depending the subject. It also varies depending on the people involved; some value proper language expression more than others.
Take me for instance. I value it a lot. Then again, I'm a English teacher who proofreads his forum posts and sends grammatically correct text messages. I don't look down on those who don't express themselves the way I do, but I do tend to assume that those who strive to express themselves well will contribute more to an intelligent discussion.