My current Top PC playing games (as of Dec 29 2005) are (potential for "emergent" characteristics in play):

This Last Weeks  
1 5 5 Battlefield 2 - Special Forces, EA Games, squad-based on-line, awesome and free server access, 95%
2 1 18 Rome Total War - Barbarian Invasion, EA Games, Creative Assembly, the standard setting RTS gets an refresh, 95%
3 10 5 The Movies, Activision, Lionhead Studios, innovative concept keeps you playing, 88%
4 2 8 Dawn of War - Winter Assault, THQ, excellent add-on, 88%
5 3 16 Quake IV, id Software, updated Doom 3 engine in quake clothes - get it! 96%
6 6 10 Black and White 2, Lionhead Studios, really Black and White 1.5 but you still can't stop playing God, 90%
7 7 9 Call of Duty 2, Activision, Really Call of Duty 1.5, 90%
8 4 7 Age of Empires III, Microsoft, latest AOE gets update, 74%
9 - 1 X3 - Reunion, Enlight, German space trim (trade/sim) get's a refresh, flight still a pain, 72%
10 8 8 Fear, Sierra, moody FPS, 77%
11 11 13 Cricket Captain Ashes year 2005, XPLOSIV, excellent update to the best cricket sim, 78%
12 9 40 Doom 3 - Resurrection of Evil, id Software, the master gets a new engine, 95%
13 12 9 Civilization IV, Fireaxis, latest sim of sims, 83%
14 - 1 Diplomacy, Atari, second recent attempt in 3 years with classic board game, 76%
15 15 123 War in the Pacific, Matrix Games, the definitive WWII strategic game, 92%
16 13 20 Domination, dreamcatcher, update to Massive Assault, best TBS, 90%
17 14 22 Football Manager 2005, Sega, latest of the best football (soccer) sim, 81%
18 10 9 Battle of Britain II, shockwave, not yet scored
19 16 14 Dragonshard, Atari, D&D goes PC, not yet scored
20 18 13 Battle for Middle Earth, EA Games, currently the best LOTR RTS, 79%