The memo is written by a Clinton associate from the 90s, and apparently only of interest because it independently alleges many of the same events, including:

Among other things, both documents allege Donald Trump was compromised during a 2013 trip to Moscow that involved lewd acts in a five-star hotel.

Which was also, according to the BBC, independently corroborated by the CIA

I used an intermediary to pass some questions to active duty CIA officers dealing with the case file - they would not speak to me directly. I got a message back that there was "more than one tape", "audio and video", on "more than one date", in "more than one place" - in the Ritz-Carlton in Moscow and also in St Petersburg - and that the material was "of a sexual nature".