Most active Facebook games of the past four weeks

(All rights reserved - Zynga)

The number of regular players required for a Facebook game to get into the top 20 rises by 1 million this week, up to a cool 7 mil. Is it the rigors of work, school, or the weather leading to an increase in activity?

FarmVille inches closer and closer to the 75 million players mark, up by 500,000 on last week, and both official news updates as well as gaming tips are making increasingly regular appearances in YouTube's most watched videos in the gaming category.

With those kinds of user numbers, FarmVille is of course the most used Facebook application, never mind amongst its fellow games. The next closest application is Birthday Cards, at 33 million users, just above Café World. The card application is of extra interest here as it is made by the developer of twelfth most active game Zoo World and offers in-game benefits to Zoo Worlders who use the birthday reminder and greetings service.

This in turn could explain why 2 million more players of Zoo World have flocked to the game, as in a rare chart move it overtakes Farm Town, which also shed nearly a million itself. Elsewhere, Roller Coaster Kingdom continues its freefall, as another million players turn elsewhere for their gaming highs and lows, and in much the same way a million Fish World players have left for sunnier climes - quite possibly ones that begin with "Happy" or end with "Ville."

Back up at the top, competition for fourth place is very tight this week as Texas HoldEm Poker overtakes FishVille after 500,000 more regular users played compared to last week's figure, as did Mafia Wars. FishVille itself has actually dropped off slightly, but parent company Zynga won't be too disappointed - they run seven of the top ten games and are no doubt working on the next big trend-follower.

Most active Facebook games on January 21 at 07:00 GMT
01. FarmVille (74,256,278)
02. Café World (30,067,969)
03. Happy Aquarium (28,135,441)
04. Texas HoldEm Poker (24,492,835)
05. FishVille (24,436,295)
06. Mafia Wars (23,483,919)
07. Pet Society (19,720,614)
08. PetVille (17,887,700)
09. MindJolt Games (15,620,998)
10. YoVille (15,016,310)
11. Restaurant City (14,753,398)
12. Zoo World (14,194,098)
13. Farm Town (13,734,275)
14. Happy Pets (11,086,214)
15. Bejeweled Blitz (9,826,570)
16. Happy Island (9,526,678)
17. Roller Coaster Kingdom (8,414,890)
18. Country Life (7,449,820)
19. Fish World (7,093,134)
20. Island Paradise (7,036,714)
Numbers in brackets indicate the monthly average users for each game.
Source: appdata.com