Also, a lot people come into the converstation late (like me).
Most of the readers may have moved on by that point, and thus
the chance of being voted one way or another is decreased.
On the other hand, this would prevent 'idle converstation' posts
from giving the poster XP.
hmmm...would it be possible to have an option for the poster
to say whether or not this post should be considered for XP?
An honor system way of seperating 'idle converstation' from
posts that are supposed to be true contributions?