Competition in an application space is good. Even in games. Look at how many tower defense or match-3 games there are. If you can make a better one, I'll play it.
Case in point, Zynga's "Words With Friends". It is the best version of online Scrabble I've played.
(Apparently it was developed by Newtoy and acquired by Zynga. And in my humble opinion, Zynga's "improvements" over the past year have had nothing to do with "evolving high quality", but are fairly blatant attempts to wrangle cash and facebook information out of me. But that's another story.)
However if you make a feature-by-feature copy of GemCraft, I'm not going to think much of you. And that seems to be what Zynga did here. They didn't build a better mousetrap, they build the exact same mousetrap and used their market position to grift Nimblebit's success.
Whenever I hear "higher quality" with no explanation of where or how that higher quality comes about my BS radar immediately starts going off. "Adding value" and "evolving" and "making X higher quality" are all phrases that have recently begun to lose all meaning and now sound like cliche corporate bullshit. Explain the how/where and I'll believe. Oh, and it's very easily to tell when you're being sincere so if a company uses it they'd better mean it or not say it at all.