You can't find those answers because there aren't any.<p>There aren't any answers because it doesn't matter.<p>It doesn't matter how many levels you have, nor how many points things are assigned. There aren't any formulas for how they add up, either, because either they add up, or they don't.<p>Gamification isn't something you install, add some hooks in at appropriate points, and magically have user engagement. It's not logging.<p>It's applied psychology.<p>There aren't answers to how many levels you have because levels are shorthand for recognition of accomplishment. Points are proxies for the player's sense of self-worth. How do you define accomplishment in your system? What are reasonable, logical, or emotionally meaningful ways to break that up? How do you break that down into learnable tasks and efforts within those systems?<p>Those aren't rhetorical questions. I'm asking you those questions. The first two establish your levels, the third establishes things that are worth points. Maybe you earn points and those let you progress through levels. Maybe they're independent. It's whatever makes sense for incentivizing your system.<p>I ran some design workshops a while back, and one of them was on applied gamification. Out of five or six groups of 2-3 designer/developers, only one really "got" it, and applied game mechanics in a way that might actually be meaningful to users.<p>The rest applied it superficially and if they had been real products, they would have failed.<p><a href="http://vi.to/workshop/20100426/" rel="nofollow">http://vi.to/workshop/20100426/</a> has my write-up of the workshop and the exercise they did, and <a href="http://vi.to/gmnotes" rel="nofollow">http://vi.to/gmnotes</a> has my notes, including the handouts and my references. I'd start with those.<p>Oh, and if one of the "famous books on gamification" is the O'Reilly one, I'd forget everything you read there. That book is atrocious. <a href="http://gamification-research.org/2011/09/a-quick-buck-by-copy-and-paste/" rel="nofollow">http://gamification-research.org/2011/09/a-quick-buck-by-cop...</a> is a good example of some of the negative coverage it received, and I never recommend it. Read books by psychologists, by people who have designed and launched video games, and by academics who do actual research and testing of their theories.