Which would be better for FCP and Pro Tools? Mac Mini 2.3GHz i7Quad or iMac 2.9GHz i5 Quad?
Actually, the most important hardware component in video rendering is videocard (GPU).

iMac has discrete NVIDIA GeForce GT 650M adapter with dedicated memory, while Mac Mini has integrated Intel HD Graphics 4000 card. The difference is jaw-dropping. Some benchmarks to prove this:


3DMark 11: 2320 points in 650M, only 604 points in HD 4000.
3DMark 11 (GPU): 2112 points in 650M, only 524 points in HD 4000.
3DMark 06: 13453 points in 650M, only 4410 points in HD 4000.


I believe, you got the point. HD 4000 is a bit less powerful than NVIDIA 610M. Quad-core processor will not matter when integrated graphics will render every frame for 2 seconds.


  Geekbench is more about CPU, than GPU. Video editing is more about
  GPU, than CPU.


8 Gb of RAM is enough for working with 4K@24fps projects.

This fall new Macs will be released with better hardware and the new OS X Mavericks will roll out with performance (CPU and memory) improvements (more free RAM for FCPX).

So I advice you to wait for a while with buying new Mac. Get better.