Oh oh! The sky is falling, 10.7.4 has been released!
https://discussions.apple.com/docs/DOC-2465 has the latest resources for updating to 10.7. With 10.7.4 each of those will have to get up to date information about 10.7.4's compatibility. But the most important thing to remember when updating to any operating system............
And remember just because there is an update, you don't have to apply it. Apply it when your other software is ready.
Mac OS X (10.7.3), * Links may give me compensation