It's also possible they could offer continue to offer the current iPad mini with modest CPU boost and no retina for $329..
And then increase the cost of the Retina iPad Mini to $399 and replace the iPad 2 slot with it.
That way they maximise bang for buck, and given a retina mini will require decent GPU, increased memory, IGZO display technology which are all more expensive components - this pricing move could allow the retina mini to have same exact specs at the bigger iPad with only size & weight being the discernible factor.
Whilst still offering a $329 model to appease those looking for cheaper option.