Harvin underwent the surgery at the beginning of training camp and hasn't practiced since then. The Seahawks sent him to New York to continue rehabbing the hip. He's currently on the regular season PUP list, making him ineligible for the first six games of the season.
Per the PUP rules, Harvin is eligible to start practicing after Week 6. Once he's cleared to practice, the Seahawks will have a three-week window to either place him on the active roster or shut him down for the season. The latest deadline to put him on the 53-man roster is Week 15.
The Seahawks have been mum on Harvin for quite some time. Harvin tweeted that he hopes to be back for Week 7, but the general consensus is that he won't be ready until Thanksgiving at the earliest. We should have more clarity on his status over the coming weeks. The Seahawks don't have their bye until Week 12.