[HBAndrew]

I'll answer what I can.

1. PhotoPlog comes with an optional hack to put a link into the posting area on forums where you can instantly insert any of your images into the post that are also a link to a bigger/full size version.

2. Not sure about this I think I saw a hack somewhere that put a button into the posting area to open a popup of the image upload page or something.

5. Highslide comes integrated, can be applied to any images and also applied to images dropped into posts via method above, check the PhotoPlog Pro demo.

6. For now I think a Gallery tab gets added to everyone's profile for 3.7x, not sure about the album stuff.

7. There is a thread somewhere named something like PhotoPost to PhotoPlog conversion, not looked too much into it maybe someone else can help you here too.