As a few already know, I use Rig3 for my blog, written by a friend and coworker of mine, Ralf. Rig3 is meant to be lightweight, work offline on your laptop and be secure by not requiring any crap like PHP. More can be found on the Rig3 site.
Anyway ralf got tired of my begging :) and nicely implemented the one page per post feature for permalinks.
Having each post on its on page allows for a certain amount of nice things:
give a link to just the one post. For big posts like our honeymoon in hawaii, they are big enough that it's a good idea to load just that post and not a monthly page with other potentially big posts.
allow loading and showing a private post in itself without sharing the rest of the posts on the same page or the entire blog.
allow adding comments for each post (comments on facebook for instance are lost to everyone else not using facebook). This feature isn't there yet, but I hope to add it soon.
allow for sharing the URL to the single post to another site, like facebook or twitter (and facebook is stupid, it'll grab any picture it finds on the post, which didn't work when I had a page with more than one post: it could take a picture from a totally unrelated post).
allow quicker loading of individual posts by RSS readers (the simple way to read a bunch of people's blogs)
I just fixed a little bug where my atom RSS feed didn't have the right links, and now everything should be good after I publish this post.