Didn't understand the meaning of the sentence. Does it make sense ?

Yes. It is an NP, not a sentence, and refers to the internet forum 2channel (see wikipedia for more detail).

Thanks, i learned something new i gess.

In general, I think it's better to have full sentences, with the exceptions being the kind of sentence fragments you'd find in conversation ("Swiss cheese? Really?"). This fragment is too wordy to be the kind one would encounter in speech, and too incomplete to be a good sample of a written English sentence.

I really don't understand this obsession people have with fulll sentences. Fragments (noun phrases, prepositional phrases and even non-constituents) are extremely common in real life, both in text and speech. Imagine a conversation where someone asked:

A "Where did you find that comment?"

B "2ch, where there are many posts praising specific companies, or, conversely, denigrating their rivals."

It is perfectly natural.

I have to laugh now that I realize that I've been on the opposite side of this conversation with another user. In that case, I was the one defending a sentence fragment. Now that I'm coming at it from the other position, where I'm not the person who posted the sentence and hence I don't know the context surrounding it, I can see that user's perspective.

I guess speakers or readers encounter any language fragments with a varying amount of familiarity with the context. In the case of this particular sentence, there are three things that make it particularly difficult to see what's going on: (1) the fragment begins with a digit, so there's no capitalization clue as to whether it was intended to be a full sentence; (2) the first word is one I didn't know (unlike, e.g., the company "3M"); and (3) there's no leading word such as "At" that might make it clear how the fragment is being used (e.g., "At 2ch, where...").

People necessarily come to Tatoeba sentences with less context than they might have when they encounter written or spoken language in a different environment. I guess the question is not whether a sentence fragment is wrong, but how likely one is to understand it if one encounters it from the outside. In this case, I see that I was not the only one who was puzzled by it. That doesn't mean that it's wrong to post such a fragment, only that it might be more generally comprehensible, and hence more likely to be translated, if it provided more clues.

I agree, CK.