Wow, this is very cool and elegant. I really like how the UI is simplistic and functional. Thank you for making it open source too. One small idea might be to

Wow, this is very cool and elegant. I really like how the UI is simplistic and functional. Thank you for making it open source too. One small idea might be to add slider bars to adjust the weights. That way, one can drag these sliders and see the rankings update on the fly. Maybe these bars (vertical?) can be displayed next to the textbox when user clicks in the textbox. Or maybe you can place the bars (horizontal) in the right column where you currently have feedback. Additional cool features might be the ability to "watch"/receive notifications for new domain names that satisfy specified weights. Maybe automatically tweet the user or implement it as an RSS feed.