Speaking as a Linguistics student, while textese is awful for spelling, it actually does improve one's communication in general. You have to be concise in what you say above and beyond chopping out vowels and consonants, because text messages and twitter updates limit how much you can say, and nobody reads long Facebook posts. Fundamentally, they're still using the same words ("wer r u goin" = "where are you going," a perfectly normal sentence) and same sentences by and large as everyone else.
Textese is only negatively impacting spelling from everything I've seen. The people who use shitty English would be using shitty English anyways, with or without text messages and the internet. It should not be accepted as a formal, academic, professional, etc method of communication, but it shouldn't be demonized as "the downfall of English" or "end end of literacy" or whatnot. It's just a different orthography for the same language.
Textese is only negatively impacting spelling from everything I've seen. The people who use shitty English would be using shitty English anyways, with or without text messages and the internet. It should not be accepted as a formal, academic, professional, etc method of communication, but it shouldn't be demonized as "the downfall of English" or "end end of literacy" or whatnot. It's just a different orthography for the same language.