I asked the arxiv administrators about this last year, and received the following reply.
Dear Scott,
Thank you for your feedback. At this time we have no plans to change the way the submission ID and the final arXiv ID are created. We developed the new submission system to be more flexible for our users who need an area to work on their submission and conduct any updates for formatting/layout/typos without being constrained on time. Hence, we can not issue an arXiv ID until the submission has been announced.
We are looking into ways to make a submission available to all the co-authors but can not provide a time frame when this feature will be added. We have received feedback that validates the need to be able to share a submission before it is announced and we are working on a solution.
-- arXiv admin
On 07/07/2010 11:38 AM, Scott Morrison wrote:
Keyword: "submit/0016922"
Dear arxiv admins,
I'm concerned about two ways in which the new submission system is inferior to the old one (mostly, though, it's great!)
First, we used to be told what the arxiv identifier would be. Now we're just given a temporary identifier, like submit/0016922. This is a problem for me, as I always used to include the arxiv identifier in my paper (usually as a footnote, e.g. "This paper is available at http://arxiv.org/... and at ..."). It will actually be a real problem, presently: my coauthors and I have 3 related papers that we want to put on the arxiv simultaneously. We'd like to be able to refer from one paper to the others, but it seems now there's no way to do this without submitting a second version the next day, because we can't discover what the identifiers will be.
Second, it's somewhat annoying that there's no way for a coauthor to see the submitted paper before it is announced. In the past, we would always have someone other than the submitter carefully check the produced PDF, abstract, etc., but it's now much harder to do this.
I'm not sure if it's possible for you to remedy either of these problems, but I would encourage you to try!
scott