elsewhen - 5:33 pm on Sep 27, 2005 (gmt 0)

one thing to keep in mind is that PPC is very different than other types of advertising. on a TV ad, for example, an advertiser pays a set amount of money for one or more 'spots'. their return on investment is just a guess at best.

in PPC, most advertisers know their ROI immediately. note that i am not talking about CPM type ads, but rather CPC ads.

imagine your typical advertiser who gets $20 for every $10 they spend on PPC. their limitation is not their marketing budget, but rather the number of clicks that google can provide. if another PPC player throws its hat in the ring, and could deliver more clicks, then advertisers with positive ROI would pursue BOTH networks.

in other words, advertisers who have a positive ROI (which i assume is the majority of PPC advertisers), would gladly throw more and more money toward any network that could continue to deliver positive ROI.

PPC is not a zero sum game.