Well, my father is a retired English professor, so you can imagine what position has been engrained into my brain...
I have to agree with you, Jon; even though there is a place for abbreviations, like SMS and very casual exchanges, in other types of discussions it just looks a bit -- sorry -- ignorant. Every time I've landed a new job, promotion or desired "upgrade," I've tried to find out what tipped the scales in my favor, so I can try to continue to develop those skills. Without fail, an ability to communicate effectively and write professionally is at the top of the list.
So, kids, stay in school!!!