User Photo Albums and Image Posting
 

Can a user post an image in a thread from a user photo album? If so, how? Or must the image be on a host like flickr or photobucket?

You can copy the code generated under the photo in user Album:
http://img401.imageshack.us/my.php?i...f865762ij8.jpg
or, if you want you can take an image from anywhere on internet.
If you want to see a image in post, not only a link, you need to use [img] tags around the link.

No, I mean the user photo albums that are generated in vbulletin 3.7, not the photo albums you'd have on a conventional photo site, like photobucket. Can the vbulletin photo albums be used as an image source?

LoRdGd meant that vbulletin gives you the link to put in a post.

Go in to view a single picture on its own, and scroll down under it (like in the link he provided you).
There's one with http://www.yourforumurl.com/picture.jpg
Copy that and paste it into a forum post, including the [img] tags.
It will show as the actual picture when you submit the post and view it live.