Apple has released iOS 4.3.2 for iPhone 4 (AT&T/GSM ), iPhone 3GS, iPad 2, iPad, iPod touch 4, and iPod touch 3. iOS 4.2.7 for iPhone 4 (Verizon) has also been released (those branches remain forked).
Both versions contain security updates. iOS 4.3.2 also fixes issues with FaceTime freezes and blanks, and problems connecting to 3G networks on iPad.
Jailbreakers are reminded to steer clear unless they want to be reverted to a stock device.
SOURCE