You'll get an email whether the article is rejected or not. I get the outside emails just as fast as I get internal emails (acceptance/rejection goes to both accounts), but I think some people said they had a delay and got the internal emails faster.
Review times vary from a few hours to a week or more. If the article isn't for a request, it will take longer to be approved. When you submit an article it goes into a queue to await its judgement

If the article is for a private request, it gets top priority because it's a guaranteed sale more or less. If the article is for a public request, it gets second preference because there is a guaranteed market but whether or not your specific article is chosen is less certain. If it's a -- I don't know what it's called -- non-request (?) article, then it gets bottom of the stack, although non-request articles are still reviewed according to which one has been there longer.
Does that make sense? That's how I have come to understand the process. I'm sure someone who has been here longer could explain it better!
As an unrelated side not, I think "queue" is a bizarre spelling. Just saying.