NV had them. Dunno about FO3 but I think not. I like it if it makes sense that a doctor would have access to the necessary equipment and training, since we have the Institute in this one it's something I think will be around. Assuming we're not already an android ofc, in which case we'll just go in for a quick upgrade.
Well there yah go, all but assured they'll be in FO4.
Project Nevada had 50 implants in all the Mojave (maybe DLCs too, I don't really know) that you could bring to a doctor and put in your body (for the right price). If you had something like 8 stamina, you could pick a perk that allowed you to put 2 leg implants in each leg instead of one (there were perks for the other parts of the body, like 8 intelligence for the head).
I can't say how much that regenerating EMP shockwave from my left arm helped me against robots and BoS.
The only thing I can ask for that goes along with all of this would be if I could see a robotic left arm. Terminator-ish.
I hope they come back
they were a fun way for some extra perks with cool effects
i loved finding the ones in the big mt and liked the effects the provided
i'm sure they'll come back, given the tech savvy of the boston area
Implants were present in Fallout series, already in the second game. As mentioned above fallout 3 had them, in a limited way, new vegas also had them. So considering that will almost certeinly deeling with institute we will propobly have option of buying implants. Personally I was never a fan of them from the theme point of view. Even thou as I mentioned they have been part of the series since Fallout 2, enchantments (especially the one's based on genes) always striked me as something more fitting our current vision of future rather then Fallout future as envisioned by the 50's.
I think that there is a fair chance of genetic enhancements being involved. It would actually fit in very nicely with http://www.gamesas.com/topic/1523978-fallout-4-timeline/page-2#entry24111362 suggestion I posted a few hours ago. Be warned, it's a bit of a long read, but it does tie together a lot of different ideas from the footage (theorised of course).
But I really do hope there will be something along these lines in terms of perks, it would be super cool. And I think it would work well with the whole idea of cryogenics.