Personalized avatars

1. Game Unlockables vs Player Unlockables (Gamification Player Progression Tips)
2. Player Engagement vs Player Involvement (Gamification Achievement Systems Tips)
3. Player Learning vs Player Progression (Gamification Player Progression Tips)
4. Virtual Trading vs Real Trading (Virtual Economy Gamification Tips)
5. Market Economy vs Virtual Economy (Virtual Economy Gamification Tips)
6. Player Engagement vs Player Retention (Player-Centric Gamification Tips)
7. Player Motivation vs Player Engagement (Gamification Player Progression Tips)