First, some caveats. The Sixers are, for now, a very patient franchise and will not rush Joel Embiid or anyone else back to action before they are healthy or ready. Therefore, it's very reasonable (and probably good for your mental well-being) to assume that Embiid will be sitting out the entire 2014-15 season. But that's not necessarily a foregone conclusion, and Embiid could very well play in the upcoming season.
Yes, Nerlens Noel sat out all of 2013-14. But, by his own admission, his body was healthy for a significant amount of time by the end of the season. Him being held out was likely a combination of over-cautiousness, not wanting to win many more games (though I don't think a few weeks of Noel would have moved the needle much), and wanting to retool Noel's shot.
Embiid, while still a project, is unlike Noel in that he did not come into the season with a fundamental part of his game broken (unless you count his foot, hey-oh!). If he is healthy, he could very well move into game action immediately without needing to rebuild his shot or something drastic like that. Nerlens and Embiid are very different players with very different health and skill situations, so drawing a 1:1 analogue of Embiid sitting because Nerlens sat seems wrong.
This season is also different from last in terms of the value of wins. Last season, losing games was a necessity in order to have the best chances of getting a superstar player to build around. This season, we presumably have that player (or enough assets to get that player in a trade). Playoffs are still not in the Sixers' horizon, but the value of winning a few more games might outweigh slipping a couple of spots in the draft, especially if the top is as big-man-heavy as it's supposed to be.
The benefits of Embiid playing this season are fairly obvious. He'll get more on-court experience, we'll be able to experiment with how he and Noel can play together, and it will keep his new basketball skills sharp. If he is ready to play, he absolutely should. But that's a big if, and the Sixers will not risk his long-term health if there is any doubt at all.
Sam Hinkie said that he had heard that Embiid's recovery should take about 5-8 months. Starting that clock from the time of his surgery, that puts his estimated return between late November and late February. Gun to my head, I would still guess that he doesn't play at all this season, but him returning to the court is certainly within the realm of possibility. What do you think?