1. Unix-based OS
2. Outstanding battery life
3. Sturdy and long-lasting; a well-maintained Macbook will outlive any Windows laptop of equal price
4. No pre-loaded crapware
5. Best trackpad in existence
6. Secure, with patches and updates for years
This more than outweighs all the other minuses, such as the overly-obsessive focus on thinness, or the outrageous cost of dongles, adapters, memory/storage upgrades, and battery replacements.