ISRC Codes: Isrc codes are embedded in the digital files and is what Itunes, etc use to keep track of your files. Sort of a digital bar code. More information at: ISRC
CD Text VS CDDB: CD text is embedded in the master files and will display the artist name, song title and album title in compatible cd players. However, it won't make your cd show up in Itunes when you import the cd. That comes from registering with the CDDB. You can read about that here.
Please display my credit as: Mastered by Nate Wood at Kerseboom Mastering
MASTERED FOR iTUNES/APPLE DIGITAL MASTERS: Apple started this program as an attempt to make their lossy AAC format sound better on the iTunes Store. Often times when you convert a WAV/AIFF to MP3, you can create unwanted artifacts such as clipping above digital 0. Thus a lot of commercial mixes can sound worse on the iTunes Store than they do on CD. Mastered for iTunes solves this problem. The process involves a higher resolution source to extract the AAC files (usually 24 bit/96k vs the standard 16 bit/44.1k). Kerseboom mastering is approved by Apple as an officially licensed MFIT mastering studio. You can read more about it here.
Recently, Apple changed the official name to "Apple Digital Masters", but nothing else has changed.