So - in your opinion what are the most secure on-line wallets, and are any of them actually secure enough to use (for the average grand mother, baker, postman, computer uninterested person, 89 year old etc)?
I guess there are no any secure online wallet like you asking and every online wallet is having chance to get attacked so if you want to save your bitcoin try cold storage like paper wallet. May be it will help you secure it
Btw is that greenaddress is safe enough? Because if Im not mistaken someone claim that greenaddress is scam because he can't even withdraw his bitcoin there. If Im not mistaken he got 10 bitcoin there and he already emailed them but no reply after 24 hours