I think they have every right to make a site containing important information about paypal regarding the security, etc. Everyone has the right to know about it!
It's one thing to be sued for trademark infringement, it's another if they can't
prove the current owner has legitimate uses or isn't using it in bad faith.
PayPal has the money, but not the power if they can't convince the proper
dispute resolution venues of their case. And as long as paypalsucks isn't
commercially exploiting PayPal's trademark, misleading intended PayPal users
or visitors for their own gain, or even attempted to sell the name to PayPal
themselves, there's nothing PayPal can do.
Read about UDRP or ACPA. It's actually educational.