i'm having the same problem (can't access website). http://www.foxbusiness.com/industries/2013/03/12/chasecom-targeted-amid-fresh-cyber-attacks/
states that "In what is growing to be a major headache for a broad swath of financial institutions, a group claiming to be aligned with Islamic terrorism has started a new round of attacks on U.S. bank websites.
Generally customer data is not affected by such attacks, however it’s been noted in the past that they can be used to create a diversion for more sinister attacks."
however, i received a text and a phone call with an automated message claiming that there are potentially fraudulent charges on my credit cards. sure enough, i called chase and was able to verify that there was a fraudulent charge to a satellite company. i have fraud protection so i'm not concerned... but i am curious if the 2 events were related.
