litecoinj is in progress and we plan to add support for it in Hive once that is ready.
I cannot wait for this to come out.
The litecoin blockchain is just too big for downloading nowadays.
Some people claim multibit is less secure than the standard wallet because it only downloads the block headers instead of the blocks. Has there been any successful attacks due to this yet? Is this something to worry about or not that important?
The main attacks against MultiBit so far have been wallet stealers combined with keyloggers. The attacker then has the necessary information to decrypt the private keys and steal the user's bitcoin. This same attack is no doubt being used against all wallets.
With the 'downloading just the headers' architecture (technically called SPV) the main extra attack is that if the attacker controls the surrounding network they can create a fake Bitcoin network and fool the user. They can then mine some fake blocks and put the user on a fake chain. If the attacker can control all the nodes MultiBit connects to and give them the same fake chain MultiBit would think it was genuine.
So far I have not heard of anyone performing this attack successfully on any SPV client.
