example - Internetmall.com (this is already taken, and not by me.. its just an example).
Then lets say i do mondera and make Internetmall.com/diamonds and for overstock make Internetmall.com/OfficeSupplies.
Would this be any worse than say Diamonds-For-Sale.com or OfficeSupplies-4-Cheap.com? Both in terms of Search Engine Rankings and how u as a person feel about looking at those urls?
Brett's search engine theme pyramids [searchengineworld.com] might also give you some insight.