I am very excited as the Nexus 7 seems to be a very nice high resolution device with excellent pixel density (315 PPI).
Poor display was my big disappointment with the iPad mini and I ended up returning it after struggling with pixelation when displaying small content (small fonts etc.). the iPad mini has a much lower pixel density (163 PPI) though I do like it's aspect ratio of 4:3 better than the nexus 7's 16:9 mainly because I read more on a tablet than I watch movies on a tablet!
PPI source info is from the list here:
http://pixensity.com/list/tablet/
Here's hoping Apple actually makes a nice upgrade when they release their new iPad Mini sometime!!!
Anyone else have any thoughts/comparisons between those two tablets?