Well, this had to come up sooner or later!

Here is the info on the official wiki.

http://planetside.wikia.com/wiki/Implants

I'm not sure what to think at the moment.
The first thing I would advise though, is do not spend SC or Certs. You get enough Implants and Chargers awarded during game-play.
Also I would stick with the Tier 1 level as anything higher uses so much power.

I am staying with level 1 'Enhanced Targeting' and collecting Implants until I have 5 of the same, then convert them to a level 2.
Be warned though. When leveling up for example 5 'Safe Landing', you do not get a level 2 'Safe Landing'. It is random

Opinion is divided over introducing these Implants. I don't think it will make much difference. They are not very powerful but help a bit depending on how you play, eg. 'Hold Breath' for sniping.