Quarter-on-quarter, overall tablet sales are expected to experience a 21.8% drop, from 43.1 million to 33.8 million units. The news isn't really bad considering that these numbers still represent a 75.8% increase compared to Q1 of 2012. Interestingly, even though there will be a drop in the global demand for tablets in Q1 2013 (compared to the previous quarter), Apple's iPad series of tablet computers is still expected to enjoy a 5% sequential increase. This means that non-iPad tablets will see the biggest drops in demand - up to almost 100%, from 22.1 million units to 11.8 million units.
Check out the chart below for more detailed information regarding tablet sales.