Zynga's best-known and most popular game FarmVille tanked on past the 80 million active player mark, 20% of Facebook's 400 million active users.
By Friday, February 19, FarmVille was already on the brink with 79.3m regulars, while just the day before it had walked away from the annual Interactive Achievement Awards having been crowned the Social Networking Game of the Year.
It looks as though a good proportion of its 3 million extra users since then have come in from Farm Town and Tiki Farm, similarly themed games which have both experienced a recent dip in popularity, amounting to 1 million less regular users combined, and Tiki Farm's absence from the top 20 this week.
At the other end of the chart, RockYou!'s Hero World looks to be well on its way to establishing itself as one of the main Facebook gaming attractions. Among other applications, RockYou! is also behind Zoo World (here at number 7), and the second most popular Facebook application overall, Birthday Cards, which has 47 million active users.
Most active Facebook games on Friday, February 26 at 16:00 GMT
01. FarmVille (82,513,966)
02. Café World (30,614,331)
03. Texas HoldEm Poker (26,704,190)
04. Happy Aquarium (26,086,577)
05. Mafia Wars (25,104,733)
06. FishVille (24,598,656)
07. Zoo World (20,166,977)
08. PetVille (19,095,551)
09. Pet Society (19,072,144)
10. MindJolt Games (18,769,733)
11. Restaurant City (14,734,769)
12. YoVille (13,552,445)
13. Happy Island (11,973,977)
14. Farm Town (11,399,076)
15. Bejeweled Blitz (10,232,301)
16. Happy Pets (10,041,364)
17. Country Life (8,327,062)
18. Island Paradise (7,608,646)
19. Hero World (7,081,724)
20. Sorority Life (5,864,842)
Numbers in brackets relate to total active users over the past four weeks.