proportionately according to the pie chart at bitcoinwatch.com "unknown" has been getting pretty massive, so new hashing devices whatever they may be are still getting turned on, big farms that are solo mining? hopefully not a single user trying to interfere with network operation? banks? the majority of blocks are being relayed by a node somewhere in europe, 93.174.55.27 , seems to be relaying 10 or so blocks a day pretty consistently ...
I believe that's 50btc.com. They consistently don't get identified but if you go look at the block they claim solving on their web site they show up there. eg. 210682, 210650 are both on 50btc.com solved list and have that IP according to blockchain.info.