Could the anonymity of tor users be compromized by these presumed bots ? As for bitcoin which could be subverted if one users holds more than 50% of the bitcoins.
Most likely not. If the bots were to suddenly turn into nodes, then there is a good chance that a large percentage of users could have their anonymity compromised.
Tor anonymity relies on the fact it is difficult to tie in where you entered the system, and where you exited the system. If someone where to control a large amount of nodes, they could (in theory) tie a large amount identities together. But this requires a large amount of entry and exit nodes.
I don't think so. It looks like these bots are connecting as users, not nodes. It might be possible to use these bots to increase/control the load on tor which may be able to facilitate an attack based on controlling a significant amount of nodes.
Tor anonymity relies on the fact it is difficult to tie in where you entered the system, and where you exited the system. If someone where to control a large amount of nodes, they could (in theory) tie a large amount identities together. But this requires a large amount of entry and exit nodes.