What does it mean to post a paper to arXiv? More specifically, a paper that has not been accepted to a peer-reviewed venue; less specifically, to any easily-searchable, time-stamped, respected depository.
Scenario A: You have a result, but there is no decent deadline for another few months. Maybe you know that a ‘competing’ team is working on the same result. Should you post to arXiv? Would that actually protect you from being scooped if someone else published the result in the meantime (perhaps at a venue that you deemed unsuitable)?
Scenario B: You are building on result B that has appeared in arXiv, but has not been accepted (yet?) at a peer-reviewed venue. You have verified the work in B. Can you reference an un-traditionally-published work?
Scenario C: You are reviewing a paper C and, being a diligent reviewer, you brush up on the latest in the area. You find a very relevant paper posted on arXiv, paper X, dated before paper C would have been submitted. Paper C makes no reference to paper X. What do you do if: Paper C seems awfully similar (similar techniques, similar results) to paper X? Does your opinion change if Paper C is a subset or superset of paper X?
I suppose as a reviewer, you would review the paper and point out paper X to the editor/PC member. But as an editor/PC member, what do you do? After all, it is possible for independent researchers to come up with the same result using similar techniques at the same time (I have seen this happen).
What does arXiving mean? Does it do more than provide an easy repository for papers? Do we (in TCS) treat arXiv differently than other areas?