BTW have you checked the code? I took a quick look and didn't see things I was expecting to see. In particular I couldn't find any code that manages wallet state in the presence of re-orgs. It appears to check that transactions appeared in the block chain, but if there's a chain switch it's not clear to me the wallet will be in the right state.
I saw a message from Thomas on his thread saying something like "can't spend coins bug happens when there's a re-org and the server gives you the wrong histories, to fix it reset your wallet and switch to a new server" .... which to me rather implies there's no re-org handling at all.
If Electrum does end up doing all SPV work correctly, how is it different to MultiBit? Just the deterministic wallet seeding?