I've used it for a week and while the high resolution display is bright and crisp, it doesn't make up for the significant loss of on screen real estate--add in the on screen menu buttons and I just find it too small and narrow.
There a few other issues that are contributing to my decision to stay with the Mini but this is by far the deal breaker for me.
It's ironic that fans of the mini say this, because fans of Android flagship phones like the One and S3, S4, and Note2 give this exact reason regarding why they dislike the iPhone.
By the way, I prefer the size of the Mini as well over the Nexus 7, but the OS and screen resolution are deal breakers for me.