There is no definitive point of transhumanistic development. If we understand transhumanism as a process of sociological, technological and cultural development, it describes a transition away from human to posthumanism. When and how this happens, we have no precise or unified idea. It has, however, to be understood as a process and not a particular point in time.
However, transhumanistic and anarchotranshumanistic thought and philosophy have arrived at a few particular premises we want to articulate as part of our goal in improving and transforming the human comdition.
The easiest starting point is that of general, all-accessible post-scarcity. Nanotechnology will give is perfect recycling and vastly improved material science; the proliferation of artificial intelligence and highly capable robotics will remove the society-wide need for manual and unwanted cognitive labor, up to all labor transhumans may not want to engage in. With automated space mining, ressources and energy will become so common, thus cheap and thus essentially worthless: thanks to nanomanufacture and automation, a desk cornucopia machine will be able to print many common items from digital blueprints. Information Sciences and Robotics will usher in an age where every articulation a transhuman may wish to pursue will be open, only constrained by the disrespect or threat to other transhumans or sophonts. Capitalistic constraints will not apply. While infrastructure will principally continue to be a thing in densely develooped areas, the minimal footprint required for advanced societies will shrink. Space construction will create plentiful new physical space to expand into - our own asteroid belt and the planet Mercury hold more than enough material to construct numbers of habitats whose living area surpasses that of earth.
The other big areas of interest relate to the modifiability of mind and body to change and add capabilities, appearances and even behavior as one agent would like. Now senses, limbs, means of communication, body plans, cosmetic appearances, new ways of thinking and old ways of thinking made easier... knowledge being more accessible. And these changes will be easier and easier to apply in shorter amounts of time.
How long will people live
Longer, approaching "as long as they want to." With genetic engineering and biotech, we will both be able to address many biological factors of aging at the embryonal level, creating humans who will just live longer and healthier (and have in-body support for other medical measures) and augmenting already-born people in the same fashion. It should even be possible to rejuvinate bodies: turning back the biological clocks and returning the body to a healthier state. Otherwise, brain encapsulation and uploading promise ways of transferring our mindstates seamlessly to a new body. With transhuman medical sciences, all physical issues will be addressable; limb loss will be artificially addressable in hours, biologically in a few weeks of cloning and tissue printing.
Will people look human
That depends on them. The humanoid morphology is advantagous in a variety of ways, and at the beginnings we will lack meaningful ways to diverge from it anyways. Most imagined bodies developed by our cultures people may wish to adopt as their one are also humanoid. Retaining a humanoid face is helpful for identification, avoidance of the uncanney valley, and interpersonal communication - our face transports a lot of emotions.
However, it‘s principally to assume that not all transhumans will adhere to human looks. Consider the furry fandom for landgoers; or transhumans modified living in water. Some transhumans will pursue as radically divergent as possible body morphologies as a point of resisting established culture. Others may not only engineer their bodies but their minds also. In the long run (centuries, effective time) transhumans will likely branch out into even outright alien panhumans.
will we eat?
Always! Even an upload technically eats - his hosting substrate requires power for computation after all, and ultimately the need for nourishment for both growth/repair and powering our bodies, as high-energy consumption systems, nessecitates that we eat something that provides us with a lot of energy and nutrients. However, eating may be as different as sitting down on an inductive charger for half an hour to charge up your robotic body.
Uploads of course, as active entities, are in entirely controlled environments, so while your physical body needs to "eat" for you yourself as the upload in a virtuality, it‘s a choice. I suspect at least physical-oriented uploads will pursue forms of simulated, recreational eating.
As an addendum, of course transhuman Techs allow us to modify what and how a transhuman eats. All the nutrients may also just be delivered in 250 milliliters of some fluid, or a big bar of raw materials and energetic compounds.
What will society be like?
...Diverse is really the only way to say. Anything more than that is dependant on what part of society you look at. But, there‘s a few things that can be said.
It will be by far more free for all people to be and do what they want, without suffering, than today. The total accessibility of technology via post-scarcity is the key to that (and one anarchotranshumanists in particular consider very important because we don‘t want a chosen few to control access to transhuman technology.)
Also, I would say society will be more educated. Manual labor will be worthless, but knowledge and intelligence will be easier and easier accessible, learning less and less hard. Everyone will be educated because it is easy, and not locked away behind unafordable infrastructures.
Lastly, between neural implants and information sciences I would like to thing transhuman societies will be more interconnected; people will be more aware of each other. To draw from popular culture, consider the Khala from Starcraft or Tsaheylu from Avatar. With cognitive interfaces transhumans will have the ability to share impressions, thoughts, emotions, eventually experiences, memories and skills. It would allow people to gain a wholesale different insight into other people. We could break down the imperfect boundaries that distort communications. And some transhumans will undoubtedly go so far with this as to form functional group minds.
Now these specific examples, they are more than a bit along; decades into actual transhuman development. But they‘re our of a time that sets a good midpoint for transhumanism - a world were people can be recognized as having a human core, even if everything around that is changing.