Hmmm,
There are already tons of good digital camera's out there...what could Apple do that would be unique? I mean digital camera's are rapidly becoming a commodity, with very little to differential from one to the next (I'm speaking specifically in the consumer level 3-4 megapixles range). You point it, shoot it, and download it to a computer. They all have red-eye reduction, they all have built in filters, and they all have 20 other similar features, and iPhoto work great with all of them already. The reason the iPod was such a success was because it paired a great portable player with great software on the computer.
Potential unique camera features:
HDD - too many battery issues, and response time issues. Plus, when traveling, I take multiple cards and if one fills up, pop in the next card.
Wi-Fi, huge battery issues. I mean a wi-fi camera paired with a wi-fi iPod storage device would conceptually be very cool, but the battery life issues would be huge.
That dosen't mean I don't think Apple has something up their sleeve that none of us have thought of...see: airport express.
Cheers,
hughdogg