It is an interesting article, Kitty. I haven't been around the sun too many times, but I don't like this new trend either. When I receive emails from people who don't capitalize it irks me. If they have the little siggy with read "sent from my cell" I do give them some leeway, but most phones have auto-correct that does the capitalizing for you! Texts are a different story.
As the blogger said, if you can't switch over from one to the other (meaning formal to casual), then we have a problem.