The etiquette and grammar of text messaging is to be included in the English Language GCSE exam, taken by pupils at the age of 16. Students will apparently be tested on common abbreviations (more on the story here).
I must say that I find that text messages I receive don't have many abbreviations these days -- certainly not as many as when texting first became popular. In fact, I find that I use more abbreviated words eg c u l8er and thx, than the people I correspond with, because I do not use predictive texting. I turned off that facility on my mobile phone as it drove me mad -- it never predicted the words I wanted to write, but always came up with a suggestion that I would never want to say (as I mentioned in this post). Even so, if I type wed, the phone will finish off the word for me and write wednesday, if I type lon it will fill in london.
Predictive texting sometimes makes texts I receive difficult to understand as people tend not to reread what their mobile has written automatically. 'He' keeps coming up instead of 'if', I find, and 'of' instead of 'me'.