We've started using markdown at work for documentation. To get it to work with vim, try using https://github.com/suan/vim-instant-markdown. It works very well, I had to hack the instant-markdown-d server to get it to show images, but it is very snappy and luanches and closes markdown files you edit in vim in your browser. I also used pngpaste to add my images while editing. You can create a vim shortcut to create an image link for you using that. Now I can use the OSX shortcuts to capture images from the desktop and easily insert links to them through vim.