In the final scene, while David is looking at files on his dad's (Michael Mancini's) computer, the character from the original Melrose Place is misspelled as "Allison" instead of Alison.
When Michael asked Sydney who did this to her (when she came into the emergency room after her accident that supposedly killed her in the original series), Sydney responded that it was someone from her past. Fans of the original series know that Sydney was run down by Samantha accidentally, whose father took control of the car trying to run from the police.