Is it possible to integrate Vanilla into an existing site? Our site is composed of a header, two columns, and a footer. All content appears in the right column with top level menus in the header and sub-menus in the left column. Is it possible to have Vanilla appear in the "content" column while retaining the existing header, left column and footer?
You COULD put it in an frame (or iframe) to achive this, but I would suggest theming Vanilla to look the same as your current site. Putting the header and footer to your current stes style should be no problem at all, and a men extension of something to addd links to the sidebar would be your best bet to duplicate the navigation in the 2nd (left) column.
This does follow the basic structire fo the standard Vanilla theme, so I would suggest doing (or at least trying) that option first.
You should only have to edit the theme (xhtml) and style (css) to get this done. It really is not a huge job and should not require any changes to the codebase.
I am not sure exactly how deeply embedded you want to get, but I have managed to make my vanilla forum seem to be an integral part of my site.
I have been using blogger to publish my site for over a year now and do not have the energy to convert it over to a more powerful system (such as wordpress). It works for my purposes just fine, and with a little tweaking of the template no one can tell I use blogger anyway.
When I set up vanilla I used my existent css layout as a template for the forum, now if you browse through my site it is hard to tell the forum and the blog are set up on two completely different systems. If you simply want your forum to seem integrated all you need is to play games with your templates.
I've made the same thing at http://www.u2.se, forum at http://www.u2.se/forum. It was pretty easy since most of the existing site was layed out with css already. The only thing I had to code outside the css was the menu with its links... which makes the coming upgrade a bit more complicated of course.