Apple has officially released update 10.7.3 for Lion. The new update fixes some bugs related to file sharing with Windows, access Directory, wifi connection disconnected after sleep state
The detail for the Update you can read from http://support.apple.com/kb/HT5048
Apart from that, Apple also makes update for Safari to 5.1.3 and provides many bug fixes & security fixes for Snow Leopard.
For now, you can run Software Update and get the latest Lion 10.7.3