People are using adsense and not even thinking of other PPC programs, it is only because google is big name. So i just thought that adbrite is a good system and people are aware of it so why is yahoo or msn trying to establish their new programs, why can't any one of them takeover adbrite. Suppose yahoo or msn buys adbrite will there be tough competition to google. There should be. I hope something like this happen so that there is relieve for publisher's as well as advertiser. The web is getting limited to adsense and everything is done according to google, we only think about google adsense and what will google like. May some other big names in the market can free us from monopoly in which we all are engrave.Infact yahoo and msn are trying hard to capture this market and make money and they will comeup with some great programs.
If adbrite went contextual aswell for network ad's, I think they could have a big impact, still, it'd take a while to compete with the big ones though..
I think amazon/alexa own adbrite they use each others sites as reference to things alexa even displays there ads