Borrell Associates estimates that real estate ad spending on the internet alone will grow to about $1.8 billion in 2005. That will comprise about one in six ad dollars spent on real estate advertising. Online real estate ad share is estimated to grow by more than half, from 10.3 percent in 2004 to 15.9 percent this year.

Borrell even pegged 2009 as the year in which real estate firms would be spending more online than on newspapers - the current undisputed king of real estate budgets. Online advertising has been hitting newspaper classifieds budgets hard among many traditionally strong classifieds advertising categories.

Search advertising seems to be the heaviest gainer from the new internet spend, with brokerage companies throwing multiple dollars per click at the medium. Interestingly, per-click pricing is varying greatly depending on both the heat of the local real estate market ($6 per click in San Diego) and the relative web savviness of the market ($3 in North Virginia).