Small yes, new not so much (the oldest domain is from 1998).
But I think you are bypassing the point here somewhat. The point isn't that it only relies on previous searches, or on previous searches at all. The point is that it is not, and will probably never be a complete database, at least not the way things work as of now.
The major difference here is your site has a nice clean interface with a very easily parseable source, something these two other sites definitely don't have.
Now, if you could manage the same results as these other sites maintaining the clean interface you have now, it would definitely be my future choice. But as long as there are other sites out there that provide more reliable results...
But I think you are bypassing the point here somewhat. The point isn't that it only relies on previous searches, or on previous searches at all. The point is that it is not, and will probably never be a complete database, at least not the way things work as of now.
Just for fun I tried a couple of other tools that boast the same feature (http://spyonweb.com and http://www.yougetsignal.com/tools/web-sites-on-web-server/) and they both found most of all of these sites without any problem.
The major difference here is your site has a nice clean interface with a very easily parseable source, something these two other sites definitely don't have.
Now, if you could manage the same results as these other sites maintaining the clean interface you have now, it would definitely be my future choice. But as long as there are other sites out there that provide more reliable results...