Addicting, but the highscores are not working properly. Playing more than once will add to the previous score, so if someone plays thrice and gets 40 points each time, that person will have a 120-score on the ladder.
Which kind of defeats the purpose.
That, and the fact that it is possible to "cheat" using the Right click.
So, yeah, the game is nice but fatally flawed to it's core.