According to reviews in major online publications.
GameRankings.com ranks games according to the reviews in major online publications. This is recent chart for top 10 GameCube games 2003 (updated January 3):
1. The Legend of Zelda: The Wind Waker Nintendo 95.0%
2. Prince of Persia: The Sands of Time Ubisoft 92.9%
3. Soul Calibur II Namco 92.9%
4. SSX 3 EA Big 92.7%
5. Madden NFL 2004 EA Sports 92.0%
6. Viewtiful Joe Capcom 91.8%
7. The Legend of Zelda: Ocarina of Time Nintendo 91.5%
8. F-Zero GX Nintendo 89.8%
9. NCAA Football 2004 EA Sports 89.7%
10. Tiger Woods PGA Tour 2004 EA Sports 89.6%
The average ratings is given from 1 - 100%. Grades in other rating systems have been converted to 1 - 100 to be comparable.