One of the bitcointalk ads says:
"Even if you use Bitcoin through Tor, the way transactions are handled by the network makes anonymity difficult to achieve. Do not expect your transactions to be anonymous unless you really know what you're doing."
In your opinion, which coin really has anonymous transaction? Is total anonymity possible at all?
The ad talks about how your IP could be linked to your transaction.
Now if you use TOR but still didn't hide your traces before, than an ovserver could link your previous transactions to an IP because all Txs are linked.
So to achive anonymity with bitcoin you need to cut the link between your transactions and your IP and in addition to that you need to unlink your transactions from your personal details. Tumblers can help with that.