Both my elder kids have been in their own room from pretty much day 1 (although we had a breathing monitor for both to reassure me.)
This bub will have to room in with us for a while (I'm not quite sure how that will go!), then it will either share with a sibling or get its own room (probably when aged around 6 months unless we can't handle it earlier). DS also currently co-sleeps with us (well for second half of the night anyway). I think our current plan is just to let DS go along as per normal and shift the baby around if having them in our room is problematic (they really will be too little to know what is going on, whereas unless I can magically "cure" DS sleeping issues in the next few months, I do not want to be trying to deal with him in the middle of the night as well as a newborn).