Why would a small paper (10 pages) with an important result take over a year to get accepted? Below is an example that I had in mind, but my question is more general: does the reputation of some authors cause their papers to be prioritized for review sooner than other important papers, e.g. the paper "primes is in p" (link below), which was written by unknown, Indian grad students?  In this specific example, a year seems like a long time to review an important -- and very short -- paper.  

http://annals.math.princeton.edu/2004/160-2/p12

Milestones

Received: 24 January 2002

Accepted: 21 March 2003

Published online: September 2004
There can be many reasons why a paper takes a long time to be published. The `official' reason is that the paper needs to be carefully reviewed and considered before the result can be accepted for publication; the more prestigious the venue, the more care is taken in reviewing the results. However, there are other factors that come into play


This is in my view the most important: reviewers take a long time to get to finish their review, especially in high-quality venues. One should remember that reviewing is unpaid labour that academics provide to the academic publication industry for (what is apparently) the right to publish. There is no real incentive to review; there are meta considerations, like standing in the community, that depend on how much you do it, but I know several successful academics that do the bare minimum.
Good results in bad packaging: even a groundbreaking set of results can be poorly structured, which would result in delay in publication (if not outright rejection). 
Politics and names do have some (minor) effect: having prominent authors/friends on the editorial board can result in a slightly faster turnaround. However, I have not heard of cases where editors have unethically accepted the work submitted by their friends, or rejected/dragged on the review process for the work of competitors.