Don't Let Me Down - The Beatles and Billy Preston played this song twice during the famous rooftop concert. From all reports, this is an edit combining the best bits of both of those performances. It is not significantly different from the B-side studio version we all know except that George's voice is prominently added to the chorus here.
I Me Mine - There are a few curious decisions made concerning this track from January of 1970. Though Let It Be re-producer Phil Spector's embellishments are gone, his extension of the song is approximated (but not exactly). And Paul's final meandering notes on the organ are eliminated. I guess since Anthology 3 already gave us the original recording at its actual length, an attempt was made to offer us something else instead, but it is a real head-scratcher nonetheless.
Across the Universe - To date, three versions of this song had been produced using the same master tape from February of 1968. This is version number four. In order to differentiate it this time, it is almost completely stripped down, leaving only John's vocal and acoustic guitar for much of the song. George's tamboura and/or sitar are added for the second verse, and what may be a swirling organ part quietly appears in verse three. I especially applaud the decision to keep the tape at its original speed.
Let It Be - The album closes with a remixed version of the title song. The new mix punches up Billy Preston's organ part, making it sound more church-like than ever on its entrance. The backing vocals by Paul, George and Linda McCartney from January '70 are used, and a guitar solo by George from another take is added, straying from the "as nature intended" concept one final time.
The exclusion of both Dig It and Maggie Mae further distances this package from the original sessions (although they do appear on Fly on the Wall), but I'm sure most fans honestly do not miss either of those spotty tracks.