You'll probably get a better response to this on the DVC board where this topic is discussed frequently.
IMO, DVC points get the best value when used at DVC resorts. That being said, you need to weigh whether or not you have the cash to finance a cruise vs. having the DVC points. If you don't have the cash for a cruise, or if it's going to be an "ouch!" to cruise, where you do have the points....well, it's a tough call sometimes.
It is nice that DVC gives you the flexability of using points for a cruise, so for some this really works well.n Don't forget there's also the option of mixing cash and points.
The $10/point thing needs to be taken in context - that's the going rate for point rental, but you need to factor in any hassle and risk associated with renting your points (finding a rentor, agreeing on terms, what if they back out, etc.). Lots of people do rent though, so the market is clearly there if you're willing to invest a little time using this method to finance your cruise.