A little more information would help before I could say one way or another whether it's definitely suspicious - though there's no real need for the buyer to request your PayPal address, and it is something that a scammers often seem to do...

You can register Hotmail, gmail, Yahoo...etc addresses with PayPal, so that in itself is not suspicious.

If they ask you to send to a different address, or give you some story about Nigeria / working on an oil rig / sending to their doctor / soldier son in a remote area...etc etc, then cease all communication and watch out for scam / phishing emails. 

The golden rules - if you are comfortable with the request and want Seller Protection - are, send the request for eligible goods that be being posted, making mention of the eBay item number. If a payment notification comes through, check that it is genuine by logging directly into PayPal (not via links in an email) and looking for the transaction on your account, post only to the address provided on the payment notification and using a registered / signature on delivery service that provides you with proof of postage.