The story of last week on Facebook’s platform was the growth of Zynga’s Café World social game, and it easily took the number on spot on our list of the top 20 fastest-growing apps. It launched on October 2nd and by today has reached more than 10 million monthly active users through a combination of cross-promotion, advertising, and, well, being a solid iteration on the virtual restaurant game concept. It grew by 8.60 million fans since Sunday, although Facebook does not appear to have updated the last few days’ worth of data so growth could be even higher now.

		Name	MAU	Gain	Gain, %	Developer
1.		Café World	10,098,584	+8,598,277	+573.1	Zynga
2.		FarmVille	56,122,407	+2,422,800	+4.5	Zynga
3.		Quizzer	6,258,466	+1,018,944	+19.5	Quizzer
4.		Status Statistics	2,879,755	+823,974	+40.1	—
5.		Causes	31,408,033	+716,774	+2.3	Causes
6.		Horoscopes	5,083,013	+647,687	+14.6	RockYou!
7.		Pet Society	19,512,235	+623,927	+3.3	Playfish
8.		Birthday Cards	21,259,390	+463,453	+2.2	RockYou!
9.		What will happen tomorrow with you?	1,603,302	+461,302	+40.4	—
10.		(Lil) Farm Life	4,737,693	+419,702	+9.7	Greenpatch Inc
11.		Mobile	12,959,209	+418,304	+3.3	Facebook
12.		How Well Do You Know Me?	10,061,070	+409,653	+4.2	How Well Do You Know Me?
13.		YoVille	18,917,129	+381,688	+2.1	Zynga
14.		My Fishbowl	5,143,462	+374,545	+7.9	TwoFishes Interactive
15.		Country Story	7,425,779	+373,398	+5.3	Playfish
16.		Animal Hunter	834,871	+364,213	+77.4	6 waves limited
17.		Restaurant City	16,200,404	+321,128	+2.0	Playfish
18.		Fortune Products	1,041,519	+314,798	+43.3	QuoteMountain.com
19.		Slide FunSpace	10,211,594	+266,791	+2.7	Slide, Inc.
20.		開心農場	3,761,044	+264,965	+7.6	ELEX

Indeed, Facebook’s platform has experienced a number of technical issues over the last couple of days that appears to have delayed reporting on many apps. The problems may have also made it so users weren’t able to access apps at all, in some cases, thereby depressing numbers on this week’s top 20 fastest-growing list.

In any case, coming in second is FarmVille, Zynga’s previous big hit. Until Café World launched, its growth was setting industry records — and it is still going strong, having gained 2.42 million users to reach 56.1 million monthly actives.

At number 3 is simple quiz-creator app Quizzer. It grew 1.02 million to reach 6.26 million monthly active users, following weeks of solid growth.

Status Statistics, an app that analyzes you and your friends’ status updates for interesting trends, also once again made it to the top 5. It grew 824,000 to reach 2.88 million, moving up from the fifth to the fourth spot this week.

And, at number 5, Causes continued its weeks-long steady climb, gaining 717,000 to end at 31.4 million.

Also notable from further down the list: At number 11, Facebook’s own mobile app continues to grow, gaining 418,000 to total 13.0 million monthly actives.