Last Month, Richard Mitchell from Joystiq says (in Microsoft reveals the top Xbox Live games of 2009) On the downloadable front, Battlefield 1943 takes top XBLA honors, followed by Castle Crashers and Trials HD. Indie Games are topped by I MAED A GAM3 W1TH Z0MB1ES!!!1N IT!!!1 (it is just a dollar), followed by Avatar Drop and RC-AirSim. Unsurprisingly, the top original Xbox game is still H...

And Luke Plunkett from Kotaku says (in 2009's Most Popular Xbox Live Titles) Xbox 360 Top Live Titles (based on UU's)

Top Arcade Titles (Full Versions purchased)

Combined sales of all Hasbro Family Game Night titles

Top Original Xbox Titles (based on UU's)

Top Indie Games (Full Versions purchased)

The Top 20 LIVE Games of 2009 [Microsoft]

And Mark Withers. (MarkWithers) from TheXBLRADIOshow (Feedburner) says (in The Top 20 LIVE Games Of 2009) Xbox 360 Top Live Titles (based on UU’s)

20   FIFA 09

Combined sales of all Hasbro Family Game Night titles

The above arcade list is based on full versions purchased.

Top Original Xbox Titles (based on UU’s)

Top Indie Games (Full Versions purchased)

And Luke Plunkett from Kotaku says (in These Were Some Of 2009's Most Popular Games To Trade [Updated] [Retail]) Xbox 360:
1. Left 4 Dead
2. Fallout 3
3. Resident Evil 5
4. Fable II
5. Call of Duty: World at War
6. Gears of War 2
7. Call of Duty 4: Modern Warfare
8. Batman: Arkham Asylum
9. Prototype
10. Halo 3

PlayStation 3:
1. Killzone 2
2. Infamous
3. Uncharted 2: Among Thieves
4. Uncharted: Drake's Fortune

2 Months Ago, Major Nelson from Xbox Live's Major Nelson says (in LIVE Activity for week of Dec. 7th) Xbox 360 Top LIVE Titles (based on UU’s)

Top Indie Games (Full Versions purchased)

These lists are based on global unique users connected to Xbox Live or in the case of Arcade and Indie Games, full versions purchased during the week.

4 Months Ago, Major Nelson from Xbox Live's Major Nelson says (in LIVE Activity for week of Oct. 5th) Xbox 360 Top LIVE Titles (based on UU’s)
1    Halo 3
2    Call of Duty 4
3    Call of Duty: WaW
4    Halo 3: ODST
5    Gears of War 2
6    Madden NFL 10 (Download the demo) 
7    FIFA 10 (Download the demo)
8    GTA IV (Purchase the full game)

14 Months Ago, Patrick Klepek from MTV Multiplayer says (in Microsoft Reveals Most Popular Xbox 360 Online Games For 2008) “Halo 3″ was the most played game on Xbox Live in 2008 according to a top 10 list released by Microsoft today, but gamers might be shocked at what else ended up on the list. The list of top Xbox game downloads also packs some surprises.

“Halo” remains king amongst Xbox gamers, but what’s “Conker...

And Ross Miller from Joystiq says (in Gears 2 stagnant on Xbox Live activity chart despite DLC) Via Xbox 360 Fanboy]
Xbox 360 Top Live Titles (based on UU's)
1 Halo 3
2 CoD: World at War
3 Call of Duty 4
4 Gears of War 2
5 GTA IV
6 Dash of Destruction
7 Left 4 Dead
8 Madden NFL 09
9 FIFA 09
10 Fable II

The above arcade list is based on full versions purchased.