There's not really any way to explain why certain words are with chat in these situations, except that they've evolved through the internet age and are just how we say it, now. So there is no source or reference for me to give you, except that this is standard usage:
I am currently in a chatroom.
I am getting on Skype (or other chat provider).
I asked him a question on chat the other night.
I asked him a question on/over Skype (or other chat provider) the other night.
To speculate as to why these patterns came about:
It's likely that you are described as in a chatroom because it contains the word room, and if we take the abstract concept of a chatroom and consider it a physical object, then you would always describe yourself as in a physical room.
You get on/log on to a chat provider similarly to how you log on to any other website; it's just how it's phrased, I don't have any speculations as to the etymology.
Perhaps we talk on chat because while on chat we are online, or because the text we type appears on the chat window.
When referring to the chat provider by name instead of the generic chat in general, perhaps we can use over similarly to how we can say over the phone; we're imagining the chat provider as sending our messages across, or over, their network.
At any rate, the above is just speculation as to why these usages are prevalent. Just stick with the rules and you should be fine, I doubt there will be a pop quiz on the origins! :)
The excerpt changes tenses because it's talking about things at different times. The first paragraph describes completed actions which took place in the past, hence the use of past tense. The second uses the present because it's talking about things at the current time or the recent past. The third begins by talking about the past, then proceeds to discuss the current state.
Think of the first paragraph like a big quotation. It's not describing any specific actual events - indeed, the second paragraph says that the first could describe several places - just some generic history. Because it's talking about history, it's in the past tense.
It sounds in the second paragraph is talking about the first paragraph. This is in the present because you're currently reading the article. Its words sound a certain way at the time you read them. Incidentally, I find this:
But this is also, and originally, Algeria, a quarter of a century earlier—the first major political crisis in the age of modern Islamism.
somewhat confusing; specifically, the aside about Algeria. I get the meaning (I think!), but I think the remark should be expanded a bit, and probably in the past tense.
The third paragraph opens by discussing completed actions in the past:
A flurry of freedom in the late 1980s gave way...
This first sentence sets the stage with some historical context. After giving us a bit information about the past, it goes on to describe the present state of affairs, appropriately shifting to the present tense to do so:
Today the country’s citizens remain powerless spectators...
Past, present and future match up with the times being described. Very generally speaking, you should work towards maintaining a single tense in your writing, especially if you aren't comfortable with the fine details of changing them. But there are plenty of reasons to change tenses. For example:
- Simple descriptions of events, as commonly seen in news, should be in the relevant tense (past events in past tense, etc).
- Literary foreshadowing might call for future tense: he gazed over his shoulder at her. He would never do so again.
- Dialogue written as spoken or thought by persons involved should be tensed as it normally would when speaking; e.g. she said, "I will go to the store tomorrow."
Best Answer
Short answer:
Well. . .
Why not follow the "crowd"?
Long(er) answer:
As long as chat to/with is concerned, chat with is way more common. This might get a little bit complicated and confusing, as I attempt to compare the patterns between the three closely related verbs. Note that pretty much 90% of the arguments here can also apply to chat.
So, for the benefit of doubt, let's take a look at ngrams about similar pairs:
Speak to/with
Talk to/with
How would I interpret this?
Chat has a bit of a more informal, more friendly overtone. The act of chatting is usually expected to be collaborative, two- or several-sided, voluntary etc. while there's less of this connotation in verbs talk and speak. In other words, we expect chatting to naturally be followed by with.
Pfft, Is that it?
No, there's more to it; let's use the irony of the name of "Quick & Dirty Tips" to quote one of their articles:
For the record,
“I talked with them and they said” returns 156k results from Google, while "“I talked to them and they said” returns 340k (!).
10 results in Google books for "I talked to them and they said" vs. 1 result for "I talked with them and they said"
First 12 results in COCA are all talk to.
Almost all of the COCA results for chat to/with are using the preposition with.
Most of the consensus in an ELU question regarding speak to/with is about the bidirectional-ness of speak with; in a similar manner to talk with and chat with. However, no upvoted answer claimed there's an obligation in correspondence with choosing the pair related to the meaning implied.
The article goes on by bringing two of the Grice's Maxims as arguments, one for and one against the use of to.
So, basically, since talk with is more correct; you should use that instead of talk to when referring to an interactive conversation.
So, basically, one could argue that talk to is better since the indication that the talk was interactive is irrelevant info and there's no harm in removing it.
Furthermore, there's this ELU question with a good answer adjacent to it. Quoting the answer:
As you can see, and as the accepted answer has pointed out, seeing chat and seriousness go together is a bit of a rare occasion. This also further explains why chat with is more common.
TL;DR:
These pair of words are observed in normal conversation: Talk to/with, chat to/with and speak to/with.
Chat with is more common than chat to by a large margin. However, talk to and speak to are more common than their corresponding phrases, also by a considerable margin.
This can be explained by three factors:
Thus, to answer the main question, chat with is more common than chat to. You may prefer to use whichever preposition you want in this case, based on the meaning you want to imply. But I suggest (not obligate) you use the with version, since people with similar interests (in your context) are unlikely not to have a friendly and casual conversation.
Due to avoidance of the stimulus "OH THE HORROR!" sympathetic response from the reader, the author did not discuss any other inflections or prepositions in this answer of his.