We’ve preached over and over how mobile is changing the digital marketing and advertising business. We’ve seen it with our own clients, and marketers across the U.S. are increasing their mobile budgets as well.

The latest report comes from Marin, a search-management software company. They predict that mobile will be bigger than desktop soon, and that marketers need to raise budgets accordingly.

One prediction is that at the current run-rates, mobile devices will account for 25% of all paid search clicks on Google by December 2012. Additionally, the share of ad spend will be 23%. Those are additions of 103% and 164%, respectively.

One of the driving factors behind all of this growth in mobile is the insanely fast consumer adoption of smartphones and tablets. In 2011 alone, Apple sold more iOS devices than the total number of Macs ever sold in the last 28 years.

Another reason for adding mobile into your business’ marketing strategy is that smartphones have higher click-through rate, and a lower cost-per-click than both desktop and tablets. Smartphone users click on ads 4.12% of the time compared with 2.39% for desktops and 3.12% for tablets. Additionally, the cost per click is only $.53 for smartphones, compared with $.83 and $.63 for desktops and tablets, respectively.

So have you decided that you need mobile yet? Well if you haven’t yet, I’ll do my best to convince you with some more data about mobile over the next few days.