I agree that CT uses a technology related to blockchains, but as I noted above, Ben Laurie has been pretty vocal in saying that the Bitcoin-style PoW blockchain isn't a technology that he favors, and I think he thinks CT is importantly different in some respects (for example in accepting more centralization in the operation of logs: an uninvolved anonymous party can't show up and "mine" a CT log event).

http://www.links.org/files/decentralised-currencies.pdf