While Apple shipped 26 million iPads in its latest quarter and Samsung shipped 14.5 million tablets, both up from last year, IDC is warning that the overall tablet market in the US appears to be reaching saturation. "It's becoming increasingly clear that markets such as the US are reaching high levels of consumer saturation and while emerging markets continue to show strong growth this has not been enough to sustain the dramatic worldwide growth rates of years past," warns IDC’s Tom Mainelli.

Worldwide tablet shipments grew to 76.9 million during the all-important holiday season quarter according to IDC, 28.2 percent more than the same period last year. However, the growth appears to be slowing. Apple shipped 74.2 million iPads during 2013 compared to 65.7 million iPads during 2012, just a 12 percent increase. That may change throughout 2014 thanks to the new iPad Air and iPad mini with Retina display, but IDC warns of "a more challenging environment for tablets in 2014 and beyond." Those challenges include high penetration rates and increased competition for consumer spending.

Amazon's Kindle Fire shipments dropped in the holiday quarter

Amazon’s tablet shipments appear to highlight some of the slow down in growth during the recent quarter. IDC says Kindle Fire shipments dropped from 5.9 million in the holiday period in 2012 to 5.8 million in the same period last year. That’s a decrease of 1.7 percent, and the figures come just hours before Amazon is due to report its latest financial results. While iPad growth has slowed and Kindle Fire sales have decreased, Samsung’s 14.5 million shipments during the holiday quarter were almost double the 7.8 million it shipped during the same period in 2012.

Meanwhile, Lenovo may have just acquired Motorola’s phone business from Google, but it’s also starting to ship more tablets worldwide. After shipping just 800,000 during the 2012 holiday quarter, shipments grew to 3.4 million during the latest holiday quarter. Despite the PC market decline, Lenovo has managed to grow its share of PCs and is the top manufacturer worldwide. With tablet saturation in the US, and the PC market decline starting to stabilize, 2014 could be the year where we start to see less dramatic shifts in PC and tablet sales.