Sorry g0ldy, but this term is grammatically correct. Although it can be used as a verb, as in "I leased a domain.", lease is a noun. And although domain is a noun, it can be used as an adjective to modify another noun, as in the term domain lease, where the type of lease is being modified by domain (used as adj.)
I like the term, and w/ prices of really good names going through the roof, and market/sales research becoming more sophisticated, I can see the domain lease market, (two modifiers), or domain leasing (take your pick) as having good potential.
My major concern here is w/ the .net tld, which is becoming increasingly more nebulous as more descriptive tlds (info and even biz) make gains towards acceptence.
So, cautiously, value at $25 whse $65-$90 retail, undev. w/ potential for term to appreciate.