Yesterday, Gartner said that mobile application revenue will nearly triple in 2011, to $15.1bn ($5.2bn last year) and much of that growth will come from 18 billion app downloads 60,000 of which are designed for the Apple iPad, which has seen sales beat expectations.

The iPad, almost a year old now, had racked up sales of almost 15 million (14.8 million by the end of 2010) and about 7.33 million of those sales came in December. That growth is set to rocket this year as this infographic shows.

Half of the iPad sales came in December. Altogether Apple sold 5x what Wall St analysts thought they would. Now Wall St is predicting tablets to soar from 15 million to 115 million by 2014 – that is a 66% growth rate! What is the risk to that kind of meteoric ascent?