If paypal accepts Bitcoin, that means that people will be able to buy a lot of things with their bitcoin... including everything at ebay.
Source:
http://thenextweb.com/insider/2013/0...tual-currency/
The major problem I see is that it will make it very hard to control illegal activities, including commercial content piracy.
Just imagine if file lockers begin to accept bitcoins, and if its very easy for anyone to log into his paypal account, buy some bitcoin using his paypal balance, then send that bitcoin to the file locker.