Sarah Jessica Parker & Cynthia Nixon were both pregnant during this season
The first episode that we see Sarah Jessica Parker's bare baby bump.
Samantha gives the yellow stone ring back to Richard at the end of the episode when she breaks up with him for the second time. In Season 6B Episode 7 as Samantha hugs Charlotte at 7:28 in, the same ring is seen on her left middle finger.
The former Trump Taj Mahal Casino belonged at the time to Donald Trump, who appeared in a cameo in episode 2.8: The Man, The Myth and the Viagra.