Are any of these guys expected back this year?
Both Harvin and Crabtree should be back working with the team sometime around Thanksgiving, and could potentially get worked back into the starting lineup over the final 4 weeks or so.
Harvin and Crabtree are much, much more valuable in keeper leagues. Back in April, Harvin was a 2nd rounder and Crabtree was a 3rd rounder in dynasty startups. Even at his best, Pitta was a mediocre dynasty TE. Add his injury to the mix, and I don't think I'd be all that tempted to keep him in a 12-team league with 5 keepers (or a 10-team league with 6 keepers).