I prefer Option B. It's easier to scan the left-hand side for who posted if you're looking for a particular person's response, and I think that it helps to create more of a feeling of having a conversation if the main/right side is focused mostly on the posts themselves -- with Option A and the layout as it is at the moment, scanning a topic is more like see user information, see post, see user information, see post... repeat.
To have the option available for a user to choose their preference would be great, I believe vBulletin allows you to code the templates like that. But for the default view, or if the option to change isn't available, I'd prefer user information on the left and post information on the right. :)
i Like A better myself. Makes the posts easier to read. This is already a pretty narrow site im guessing like 780 or something but with the user name on the side, the area for posts is going to be really narrow.
Looks like we're making it an option then, doesn't it? :) Can't implement one and not the other if it's quite evenly matched. It just wouldn't be fair. Thanks for giving us extra work! We love it really.
The man who comes back through the Door in the Wall will never be quite the same as the man who went out.