I think positive because like you said there's the "Lol tru dat bitch" spearkers as well as the grammar nazis and you can meet both and all kinds of people on the internet. In general it exposes you to a lot more knowledge easily or maybe quickly is a better word.
I like learning about how other people speak.
Somewhere in this video I think they talk about this sort of thing. (If not, one of the lectures by this professor he talks about it somewhere, but briefly. Even if you can't find it these lectures are really interesting. (To me anyway...)
http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-868j-the-society-of-mind-spring-2007/audio-lectures/lecture-9/I said that the Internet overall probably has a negative effect on people's use of the English language. Prior to the Internet, if you wanted to read the news, you had to get a newspaper or magazine. Similarly, if you wanted to research something, you needed a book or an encyclopedia. All of these older media are copy-edited before they are published, which removes most grammatical mistakes.
With the Internet, anyone can post anything online for everyone to read, and much less of what is posted online is properly copy-edited. The result is that a greater percentage of the material that we read is informal and is therefore littered with grammatical errors, colloquialisms, and shorthand. For a person like me who does a lot of formal writing and knows how to use proper grammar when necessary this is okay, but there are many people out there whose knowledge of grammar is only as good as the material that they read.
You have some good points. However, I disagree because of a few things;
First of all when Wikipedia first came out all the teachers (I guess a lot still do) said “this is terrible… an encyclopedia that anyone can edit, it goes without saying that it’s useless. Any moron can put a total lie up and it’ll be recognized as truth.
But theoretically if the admins of a site like Wiki are large in number and variety and diligent this type of encyclopedia could be much, much more accurate and effective than a book. First of all a book is written by a small group of people who claim to be knowledgeable in some area of expertise. But they could be wrong. And once the book is printed, that’s it. The internet can be edited over and over again, as it needs to be and should. And you have experts from basically around the whole world to verify knowledge much better imo.
But back on the subject of grammar, I never liked strict grammar in the first place. For one thing anybody can say something that isn’t a sentence like this:
“Where’s my phone?”
“On the table.” <<that’s not a complete sentence but you understood what I said just fine.
I’m not so sure about other languages but English has a crap load of problems.
They’re
There
Their
Do I really need to explain? Who invented this crap? Who said ‘yeah those three words are fine, they’re not confusing at all let’s stick with them. Foreign speakers won’t have any trouble learned our language. Or how about silent “e” or the I before E except that rule doesn’t always hold either? “comb”, “déjà-vu” < that’s not even really English!!.
I should say that the main reason I don't feel obliged to use correct grammar is because of all these ridiculous twisted rules. Not much in English is very rational. When learning the language, you can't "sound-it-out" like they said in Elementary. You can't expect anything.
Japan has two characters that change under circumstances. German has something too I forget what it is, but from what I’ve seen English is one of the worst. Why did it become the most spoken language ever? (rhetorical question)

Japanese has a lot of neat things, one is; KA at the end of a sentence makes it a question. think how useful that is. You can just add ka at the end of any sentence and make it a question. Can’t do that in English.
[end of rant]