Personally, I group my "internet speak" (for lack of a better term), into two categories. Forums/Email are in one category, and IRC/IMs make up the other.
If any of you weren't already aware, I am a grammar nazi.
Much like Notnamed (damn you for changing your avatar; it took me a minute to realize who it was.
), I take the time to punctuate and capitalize properly on forums because it isn't real-time. This applies to Email as well.
Now when it comes to real-time programs, like IMs or chat, I'm not as particular. Don't get me wrong now, however, because I always find the time to use proper grammar, but I generally won't bother capitalizing because it takes too much extra effort to reach for the shift key.
I understand everyone isn't an English major--hell, I'm not either; I just play one on the internet--so I don't expect perfect grammar. It would be nice if people could spell out words like "you", but I can live with that on occasion. My biggest issue is when people use such obscure or ridiculous spellings that it takes me time to decipher what it is they're trying to say.
The following is an example of how not to type:
1st. u cannot sleep 4 3 yrs i think afta 3 weeks u wud die of stvation 2nd if u didnt stick ure tongue out u cud never moisten ure lips. oh and try 2 not lick ure lips wen eating a doughnut it is the hardest thing i nthe world!
That puzzles me, yet it saddens me just as much.
Now, yes, I will admit I use the occasional "lol", but I figure that is pretty common internet usage by now. After all, it does exist in the dictionary even.
That is all.