A (small) issue in astro these days is when tp put the preprint up on astro-ph. Let's not quibble on whether one should post it on there. If it ain't on astro-ph, it does not exist. But there seem to be two schools of thought on when to post: when accepted to the Journal (after all the referee's comments etc are incorporated) or when submitted to the Journal. It can make quite a difference. Option A is the safe bet. The manuscript has been vetted and this is how it's going to appear in print. Option B is riskier and generally thought to be associated with a more cut-throat approach (first!). So I generally was not a fan of option B until I heard the following argument: referee rapports will not catch everything and a preprint on astro-ph is a way to get feedback from people before the paper is fully official and in print.
This latter vulnerable approach (here is my work, please comment) is one that I could get behind. So as of coming Monday, my first submitted paper will be on astro-ph. My co-authors have already thoroughly vetted it so it should be ok. But I welcome anyone's feedback (ducks behind couch).