Unfortunately this is a common problem with online brokers and banks. 3 months ago there was a segment on the 6 o'clock news with a guy who had the same exact thing happen to his Etrade account. They told him it was his fault for not having a firewall and protecting his computer from hackers. The legal analyst they interviewed for the story agreed it was the customer's fault and responsibility. Sorry,

hopefully your case is differnt.
Check the terms of you agreeement, you may not be able to take them to court, there was probably a clause in their agreement for binding arbitration.
SIPC won't insure this, SIPC insures if Broker or clearing firm go bankrupt and company doesn't have enough funds to pay back customer accounts.
Etrade is currently installing a new policy, every customer will be receiving a RAS token, it is a little device that spits out a new 8 digit number every 20 seconds, and to log onto to your account you need to type in the current 8 digit number for that 20 second window. This way only the person who has this device can login to the account. It is an attempt to stop what happened to you.
To wire the money out of your account, the account the money was wired to would have to be in your name also. They can't wire the money to an account with someone else's name with out written authority from you. Check into this.
They probably won't give you any info or let you into the account because they are still investigating it, maybe they already involved Feds because the same person did this to multiple accounts. Also their lawyers want them to cover their asses and not give out info that makes them liable. Also they can't be sure you are you and not the hacker/imposter who stole the funds.
Sorry I don't have better info for you.