CyanogenMod 7.0.3, an incremental release for CM 7, is now live at cyanogenmod.com. While we're waiting for the official changelog from Cyanogen himself, I can tell you that it does not contain Android 2.3.4 (it's still based off 2.3.3) - that's been saved for CM 7.1 (if you can't wait for 2.3.4, you can update to it by using the nightlies). It does, however, contain important security fixes, among other things.