Due to constraints of technology, I would say that a Retina iPad mini coming early in 2014 is a good bet to take. In contrast, I am taken aback by NPD’s prediction of a revision in the third-quarter of this year.
What meaningful additions can Apple make to an iPad mini in 2013 that makes a product refresh worthwhile? I’d argue there are none, making a refresh very unlikely this year. Margins on the Mini are still very compressed, which I think makes Apple very resistant to doing a refresh soon.