I knew CoD2 wasn't doing that well but here's the proof. 2,000 less servers than CoD.

1. Half Life 29735 servers, 66263 players
2. Half Life 2 22978 servers, 55843 players
3. Battlefield 2 7098 servers, 25188 players
4. Wolfenstein: Enemy Territory 3580 servers, 11184 players
5. Unreal Tournament 2004 2623 servers, 6172 players
6. Americas Army: Special Forces 2130 servers, 5461 players
7. Call of Duty 3311 servers, 5341 players
8. Call of Duty 2 1379 servers, 5053 players
9. Neverwinter Nights 1187 servers, 3079 players
10. Quake 3: Arena 1855 servers, 2661 players
11. Soldier of Fortune 2 1176 servers, 2520 players
12. Medal of Honor Allied Assault 1984 servers, 2307 players
13. Unreal Tournament 2237 servers, 1853 players
14. Medal of Honor: Allied Assault Spearhead 1306 servers, 1776 players
15. Battlefield 1942 863 servers, 1681 players

There might be only 2000 less servers, but only 300 less players.

So a lot of empty CoD servers and a few CoD2 servers packed then.