This question is more applicable to journals (esp. in non-CS fields) where the turnaround can be much longer than conferences. Basically how do you decide whether to cite related papers made available/published after you submitted your paper or put it on arxiv? Do you impose a temporal barrier on information based on some date or do you adjust your paper (esp. literature review) as things become available during the review process? Is it OK to cite a paper that cites another paper which in turn cites your arxiv preprint?