Its perfectly fine. Why do you think there are so many Minecraft clones around?

/sarcasm

Though I agree, its like "I might be stealing Wolfenstein 3D's ideas, my game will have weapons and it will be played in first person!"

I'm against clones in the sense of those games that only strive to get to the sample place exactly the same way as another game. That's a rip off. But honestly, who never thought "Hey, I like this game and I know how to make it better!" ?. I'd say that most game ideas (or ideas in general) begin with that instead of coming up with a game idea out of the void.

This wasn't posted in the 'Business Forum', it was posted in 'GDnet Lounge'. If it is now in the business forum, then a moderator put it there.

Yes, because you asked a question about the law, so this is where it needed to be asked and answered.

What is an INTP?

http://personalityjunkie.com/08/intj-vs-intp-type-differences/

 

My advice: strip the game down to its essence (why you think its good on paper).
Then build a new game from the ground up based around this concept.
Ship it, and make it grow.
Watch and profit!

 
Keep the essence, at the game mechanics level, but ensure you strip away all the distinctive elements that someone could sue about: names, plot, user interface layout, etc.
Don't let your game be recognizable as a clone of their game, because shoddy workmanship is sadly correlated with a tendency to compensate for lack of success with litigation attempts; don't tempt people you should presume to be dangerous and unreasonable.