I'm just thinking out loud here, but there are at least a few areas where MorphOS could shine in niche markets. They aren't without hurdles in place though.
One of them would be the group of people fed up with the security problems facing Windows. There are a lot of people who try Linux, hoping for an alternative, but find it overly too complicated. MorphOS could really shine here, if it wasn't for the lack of an up to date web browser (most of the other apps people would want/need are on the horizon.) I don't see the cost of the hardware being a big stumbling block at the moment. A good number of folks would pay premium for the added sense of security along with an operating system they could actually use without feeling too intimidating.
As for at least another, anyone heard of Feevo or XBMP (now XBMC)? I remember hearing something about Microsoft making a version of windows just for media stuff too. The problem (as of the last I read about it) with Microsoft's solution is that the computer can't really be used as one (a computer, that is), unless you're dualbooting. XBMP/XBMC is cool, but just running it violates the DMCA. As for Freevo, well, Linux isn't exactly a fast booting OS. With a MorhOS port, you can keep the computer functionality, boot in to it fast and don't have the DMCA (for where it applies) lurking in the shadows. I think for this to really shine though, we need some hardware assisted DVD playback. (Couldn't an extension be made for CGX to support this?) It would also be helpful if there was a larger filesize limit. (TV out would be a must have for this.)
Sure, these are small (niche) markets, but compare to the Amiga market, they're infinitely larger. There might even be enough of a market to see the cost of hardware dropping.
Enough rambling.. Back to filling my veins with caffeine.
