Good things come in mini packages. This mini is packing:

2.5 GHz dual-core Intel Core i5 or 2.3 GHz quad-core Intel Core i7

500 GB hard drive or 1 TB hard drive configurable to a 1 TB Fusion Drive or 256 GB solid-state drive—upgradable with an extra hard drive or SSD using our dual hard drive kit

4 GB, 8 GB, or 16 GB of DDR3 SDRAM

Intel HD Graphics 4000

Thunderbolt and HDMI ports

SDXC card slot

This mini lacks an optical drive, just like its predecessor.