With a reported 71% jump in year-over-year revenue, the explosive growth of lead generation means it's one of the hottest sectors in online advertising in 2006. As major brands continue to enter the market in 2007, it's vital to be able to distinguish between top providers who will deliver a quality program -- and lower quality players who will waste time and marketing dollars. To aid in this effort, I've assembled five imperative questions to ask your current or potential provider -- and the answers you need to hear.

The current stampede to online lead generation is understandable, given that lead-gen and related activities like co-registration are the fastest growing segment of all Internet advertising spending, according to the Internet Advertising Bureau. Nothing else even comes close. For now, let's focus on co-registration, which can be a golden goose for many Web sites and advertisers.