Thing is, for some connections it is the IP address of my machine, whereas for others it is the localhost. Just curious to find out what the differences could be.
Both localhost and 127.0.0.1 point to the local network.
Actually they point to the
local machine. It's the loopback address:
https://en.wikipedia.org/wiki/Loopback_addressI'd also like to add that Bitnodes doesn't list Tor nodes at all; therefore as dkbit98 pointed out, when Bitnodes show ~15,000 nodes, it's probably 3x or higher in reality.