Security wise Paypal is a bit weak because all that you need is password and you gain the access to the account ....
Unlike other processors and digital e currencies which operate on pin mailed to your account or individual pin ... and confirmation messages stuff ...

But the interesting thing is that as soon as there is any transaction made in your account PP sends you a mail regarding that unknown transaction so by seeing that you can know that your account has been hacked... And you can always get it through charge back