Anyone else seeing very faded sidebars like that? I don't know what would cause that; if you have the technical skills do inspect it on your end to find out, please let me know.
Can you elaborate on what specifically you like better about bustaname?
Sorry to worry you, I darkened the sidebars so as to suggest that they are a bit "loud" compared to the primary content. They only contain tertiary tasks, though I suppose that's arguable for the legend.
I like BustAName's AJAX-powered containment of the features, though a redesign is in order.
Aside from design considerations, you may want to look at how you can point users in the right direction before they arrive at the results page and then have to starting filtering or start over to achieve more desirable results.
For example, you could offer corrections to potential typos. If a typo is not detected (or disregarded), provide some likely criteria for the eventual results, starting with common scope limiters for domain names.
I acknowledge that your product name is "lean" but there are possibilities for domains that I can safely opine that a significant majority of users will be uninterested in, and I'm not sure from the results page effectively communicates whether those have been sifted out or not.
Seems there is still demand, and room, for simplified domain search. Cheers!
Superior in practice: http://www.bustaname.com/word_maker
Though I prefer where you've started.
Also, your favicon is... suggestive of something entirely different. Perhaps a less literal image would be better?