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I think by the fact that you are asking wether its worth developing, probably answers the question for you. If you knew it was worth developing, you would be developing it by now.
I only develop a domain if I actually get excited about it. If i have to think about it, I usually dont bother.
I would think so. Develop it to rank it and get the AdSense revenue, and once you have the visibility your chances of a nice sale increase. What's to lose?