The new Nook HD was so obviously designed to be just slightly better than the Kindle Fire. It has an HD screen and a slightly faster processor, otherwise the specs are very much the same. Personally I'm starting to have trouble diving much difference between one tablet and the next. I guess what they say is true 'it's all in the apps'.
The Nook HD + seems to be not a huge upgrade over it's smaller companion. Bigger screen, and slightly more impressive specs. You have the option of getting up to 32GB of storage on this model. Meh.
The one thing I'll say about these two devices is that he price seems about right. $200 and $300 respectively.