Emerging Mobile SMS Ads ?

Recently I discovered a platform for making SMS ads, which is quite different from the traditional ads platforms.
http://www.zeepmedia.com/

It seems that sms would be quite effective since most people will look at it. And also the site says "You set your own bid in our auction and only pay when someone responds to your SMS ad."

According to

comScore Reports October 2012 U.S. Mobile Subscriber Market Share

http://www.comscore.com/Insights/Press_Releases/2012/11/comScore_Reports_October_2012_U.S._Mobile_Subscriber_Market_Share
Mobile Users top content usage is still SMS and it is growing!
Oct 2012 shows 75.9% of using SMS while only 63.8% as of Feb 2010

It would be a growing advertisement market and it is promising.