Post-PC era? Here we come: According to new data from NPD, tablet PC shipments are expected to grow from 72.7 million units in 2011 to 383.3 million units by 2017. For comparison purposes, worldwide PC shipments for 2011 were 352.8 million, after seeing a 6% decline in Q4.

While those numbers are remarkable enough on their own, what’s really interesting is where much of the growth will come from: the emerging market.

Emerging markets are expected to account for up to 46% of worldwide shipments by 2017, up from the 36% share in 2011.

“The emerging market opportunity for tablets has been flying under the radar mainly because the device brands aren’t household names and there are concerns regarding the sustainability of the market,” says NPD Senior Analyst Richard Shim. But the firm believes that won’t always be the case. “We are beginning to see investments by some of the better known brands in developing regions, and we expect this to not only continue, but to flourish as competition improves,” he notes.

The tablet surge won’t be courtesy of the iPad alone, especially in these emerging markets. Specifically, the report cited the introduction of new brands like Aakash in India, for example, as well as older brands like Dell, as contributing the overall tablet growth.

China and the Asia Pacific regions are leading in terms of tablet penetration rates in emerging markets at present, but Brazil, India, Russia and other countries are also becoming bigger forces, says NPD. And the key to unlocking this growth comes low-power processors and tablets with price points under $100.

In addition to the growth in emerging markets, NPD also believes that other growth will come as the tablet platform itself evolves through technological advances. That evolution comes first from higher pixel densities, then later from higher performance. The changes will segment the market into “premium” and “value” category tablets. (Any guess where iPad will be?)

Believe it or not, it even sounds like Microsoft might still be in the running as a tablet competitor, if NPD’s related survey data is to be believed. According to a survey of U.S. commercial tablet owners, 39% indicated that having a Windows OS option as a part of their next tablet purchase was “very important” to them. But let’s wait to see which tablet they end up buying – saying and doing are often very different things.