Correct. Apple calls it 4.2 for the average joe but the file is actually 4.2.1. There was a critical bug found at the last minute before going public and they never renamed it on the public site.
If you had installed 4.2 GM before the WiFi bug was discovered (as I did), iTunes wont "naturally" update to 4.2.1. If you absolutely want to be 100% positive you have 4.2.1, do this.
Download the firmware here, go into iTunes and shift (Windows key, sorry don't know what Mac key is) and click restore and then locate the firmware you downloaded.
If you had installed 4.2 GM before the WiFi bug was discovered (as I did), iTunes wont "naturally" update to 4.2.1. If you absolutely want to be 100% positive you have 4.2.1
If you had installed 4.2 GM before the WiFi bug was discovered (as I did), iTunes wont "naturally" update to 4.2.1. If you absolutely want to be 100% positive you have 4.2.1