This show did pretty well in the ratings for week 2 :
From Marc Berman of Mediaweek magazine :
CBS was close to opening week levels from one week earlier with its combination of How I Met Your Mother (Viewers: #2, 7.88 million; A18-49: #2t, 3.0/ 8), The Big Bang Theory (Viewers: #2, 8.58 million; A18-49: #2, 3.4/ 8), Two and a Half Men (Viewers: #2, 13.38 million; A18-49: #3, 4.6/11), Rules of Engagement (Viewers: #3, 10.54 million; A18-49: #3, 3.9/ 9), and CSI: Miami (Viewers: #1, 14.88 million; A18-49: #1, 4.6/11). The positive news for The Big Bang Theory was growth out of lead-in How I Met Your Mother of 700,000 viewers and 13 percent among adults 18-49, and a performance close to its week-ago debut.
The ratings in the all important 18-49 year olds fell by about 9% that is not bad after last weeks sampling, and it managed to stay ahead of How I Met Your Mother, and improving on HIMYM by 13%. It also beat NBC's critically acclaimed show Chuck that finished at a 3.1 rating. Chuck's ratings were off by 14 %.
As long as this show keeps beating How I Met Your Mother and Chuck in the ratings it is a certain keeper to stay on the air.