Time for a little more Apple speculation; according to AppleInsider's sources, the Cupertino company is discretely flaunting prototype Mac mini units with HDMI ports, rather than DVI. Two people "familiar with the matter" claim that the updated Mac mini has both HDMI and Mini DisplayPort, with no other aesthetic changes to its casing.
As for internal changes, at least one prototype has apparently been running NVIDIA's MCP89 chipset, the successor to the MCP79 aka GeForce 9400M. However thanks to Intel's ongoing legal battle with NVIDIA, there'll be no way for Apple to pair the MCP89 with the latest Core i3, i5 and i7 processors; it's unclear what Apple will do in response to that.
Elsewhere in Apple's prototyping labs there's apparently a proprietary mini DisplayPort to HDMI adapter, which was originally created to accompany the iMac back when Blu-ray was intended to be included with the all-in-one desktop. However the drive technology never made an appearance, and it's unknown as to what Apple might do with the adapter cable.