Top 3 charts in US are Flappy Bird clones. If they will stay there as much time as Flappy Bird or more it is called succes? 
Man... Top 50 is a success. =)
Top 3 is a huge success.
Dont get me wrong. I still think that clones are not valid.

Maybe I am wrong.
But I really do believe that to achieve a high number of downloads / profit you must create something new.
Even a clone, but not on the same moment as one has been on top charts, but a clone on a different timing.
This is true Gfalc.. but it's also 'trending' now and many people want that fix.
I doubt any clones will get half as much success.. but if it's good enough with a different twist (I have an idea I'm try to do in a week).. it -may- do good enough.. as long as it's free - people are willing to try- and if it's addictingly simple, then who knows. But it needs to do more then just a straight clone for sure, and still be appealing
You are right.
As the guy above, who did correct me (again, I am open to new facts / ideas).
Maybe the trend will still go on.
Specially because the original (at the moment - Flappy Bird) was removed from Apple Store.
Being removed is a new scenario. People wants to try that feeling and cant. Maybe this actual moment is actually a perfect one for clones.
Who knows?