From this episode onward, the screen credits for the cast were modified to remove the ranks of their characters, except for Kate Mulgrew as Captain Kathryn Janeway.
This is listed as one of the "Ten Essential Episodes" of the series in the 2008 reference book "Star Trek 101" by Paula M. Block and Terry J. Erdmann.
Prior to Seven of Nine's introduction, the only Borg whose voice did not sound electronically modified (while part of the Borg Collective) was the Borg Queen. In I Borg (1992), Third of Five/Hugh did not have an electronically modified voice, but he was not part of the Collective during his speaking parts.
First appearance of Seven of Nine.
When Seven of Nine tells Janeway and Tuvok about the Multi-Kinetic Neutronic Mine, the visual diagram displays a model that has the exact same configuration as the renegade Borg vessel from Descent (1993) and Descent, Part II (1993).