Why is everyone only looking at the number of shares they submitted to a particular round and deciding they got screwed? Not all shares are equal - you have to divide your
score by the total score for the round to determine your reward, as Slush clearly points out here:
https://bitcointalk.org/index.php?topic=1976.msg50002#msg50002reward = user score / total score * 25
The scores for round 17925 probably got reset (normalized) right before it ended, resulting in many people with very low scores and only the few that managed to squeeze in a share or two right at the very end getting most of the reward.
If you bothered reading any of the posts you will see that they're not.
Using the correct calculations peoples scores are off by a degree of an extra 0.0000 ... thats more than the normal "shares near the block discovery are worth more" debate.