Don't confuse synthetic benchmark scores with real world performance.
Macworld has some real world benchmarks for the past three generations of Mini's located
here, and nowhere is the current 2.3 i7 even close to being twice as fast as the current i5. In fact, you really need to go from dual core Sandy Bridge to quad core Ivy Bridge to see a significant difference. By comparing each model's results from that page, it's pretty obvious that the next base model Mini will slide in very similar to (if not above) the 2.3 i7 plus have MUCH better graphics.
For most people, the current i5 Mini with a SSD and 8GB of RAM is more than adequate.