I've been playing around with it a bit. I have 3 comments/suggestions.
1) It's a bit jarring to me the way that it first displays all of the domain names, available or not, and then removes the unavailable names. It'd be better to hide the unavailable names from the get go.
2) I'd love to be able to filter the results by character length. I want to enter 10 related words and see what it can come up without having to wade through the ridiculously long names.
3) I'd also love to be able to search for non .com domain names. Specifically, showing me matches that take into account the extension would be awesome. For example, extradelicio.us or automagical.ly.