I have had some success putting up small sites for keyword.com websites with little competition and ranking in google with virtually no backlinks. my question is how many searches do you believe you need to make it worthwhile to profit from search engines "lust" for exact keyword.com domain name?
quick followup, My experiences are with exact longtailkeyword.com but could I get the same effect by using a .net or even .info?
As to your first question, it would depend on what niche you are targeting and how well your site converts. With some niches you can make a lot of money with relatively little traffic. For others, you need lots of traffic to do well. So you might have to approach this on a trial and error basis. Try a few different niches and see what works. Then you can get a basic idea of what you can earn with a certain amount of traffic. As for using other tld's, they should work but I would watch out for ones where the .com is already ranking well. The keyword research site in my signature is a .info and it had no problems getting rankings.
100 visits per day are sufficient to test any niche if it is profitable or not. Mention how competitive your keyword are.
I don't think he just wants to test the niche, I think he wants to jump right in. I think he just wants to know what kind of keyword search volume you should be targeting.