I remember (way, way back), when I first signed up with PayPal, they did a test like that. However, I knew about it beforehand, so I wasn't concerned.
I've been using PayPal for a very long time now and have never had any problems with it. The only thing to watch out for, as with any online site, is phishing emails. Don't ever give your info in response to any email.
I haven't had any scam emails in a very long time either, so maybe they're got a handle on it nowadays, but it still pays to be vigilant, when you're new to something.
"" A little learning is a dangerous thing."-Alexander Pope