Last episode on 31.01.2012: S04E03 (Episode: Community)

Upcoming episodes:

S04E04 @ 07.02.2012: airs in 2 days. (Episode: Identity)

S04E05 @ 14.02.2012: airs in 9 days. (Episode: Legacy)

S04E06 @ 21.02.2012: airs in 16 days. (Episode: Integrity Check)

S04E07 @ 28.02.2012: airs in 23 days. (Episode: Fallout)

S04E08 @ 06.03.2012: airs in 30 days. (Episode: God's Work)