Yeah, I guess it depends on the method of feed generation. For example, with Worpdpress it's a simple matter to include the image thumb inside the "excerpt" box, then set your feed to excerpt mode. I know a lotta people have issues with going "full article", and I know the SE's do too. Some other feed generators are a little trickier to tweak than a WP blog. But a few of the ones I like I know are coming out with updates very soon that will make it easier to do some things like include a thumb in the feed in excerpt mode. It's a great time for RSS.