Kudos to Harmony Tan. I thought she was done for in the final set when she fell behind 5-4. Even if she had lost today, she gets credit for lasting this long against Serena Williams. Granted Serena is pretty rusty right now, but she is still a dangerous opponent.
As for Serena, I suspect that this was just a warmup for the US Open this fall. She'll be used to playing in majors again, and she'll most likely go farther. Note that she's not completely out of Wimbledon yet. She will be playing doubles with Jamie Murray.*
*Correction: Venus will be playing with Jamie, not Serena