I actually blame spell and grammar check on much of the loss of llanguage skills. I, like most people, use it myself. However, it makes me complacent on the proofreading thing, and I sometimes feel like my writing skills are slipping as compared to where they were pre-computer.
At least in my case, my parents and I would disagree. The immediacy of the feedback of spellcheck(even when it still had to be run manually) actually improved my spelling.
I would think that the Internet and electronics have probably done as much to improve literacy, grammar, and spelling as they have done to damage it. And there's probably a healthy bias effect that we're simply exposed to more of it.
Selection bias, very good point. Rose tinted glasses and all that.
I've been looking at a lot of Civil War, and even WWI and WWII correspondence and it's rife with grammatical and spelling errors too. However, it sort of gets a mental pass from most people as being "quaint".
I've seen the same as well, even in newspapers. And that's after accounting for language shift. With the really ancient languages things can get even weirder - things like them not bothering to write vowels down.
The printing press and cheap paper reduced the cost of additional letters, so vowels and such could be inserted for little cost, bringing written language closer to spoken. Indeed, we're as regular as we are though the persasive effects of cheap media, universal compulsory education and the multi-century efforts of people like Webster.
With the spread of smart phone messaging though, I predict a shift towards language that's easy to type in and have autocorrect 'fix'.
