The site looks good and works well. However, are ~4000 nonmember domains and ~13,000 member viewable domains "all" one can get? That is, Domain Pigeon pre-selected these names? If so, that is certainly a different approach, going for quality instead of quantity(since 13,000 domain names is certainly a drop in an ocean of possible domain names not taken yet).
I kept looking for some sort of associative search box, for example one could enter "LISP" and find "LISPy" names.