Film scores are often different from the commercially released soundtracks, and in years past, sometimes the "score" version of the music becomes available ahead of awards season in a "For Your Consideration" release - in the past, found only on promotional CDs sent to select people in the industry, but more recently, also made available online in MP3 format.
Keep in mind, the commercial releases often undergo additional mixing and mastering, and are usually the best representation of the intent of the music. But those in-the-film "For Your Consideration" mixes are, to me, an interesting peek into the creation process.