Some questions I've had since forever:

1. Would our current technology be able to detect life on EARTH ITSELF from "just" as far as Pluto?

2. If an alien probe was sending pings towards Earth, deliberately or not, from as far away as Voyager, would we be able to, detect of course, but notice it?

Regarding 1, yes, we think we can identify based on their atmosphere's composition and temperature habitable planets orbiting other stars, so the distance from Pluto to Earth is easy, and one could certainly identify Earth's radio broadcasts and so on from the distance of Pluto with the right antenna.

Regarding 2, depends entirely on the pings. Their doing it deliberately would certainly increase the odds. :)