The PlayStation 4 will still have a optical drive according to a interview between Kaz Hirai and MCV. Hirai has ruled out a download-only future for the next generation PlayStation console as Sony’s business will always require a physical discs in one way or another, despite being the first one to release the download-only PSP Go.
“We do business in parts of the world where network infrastructure isn’t as robust as one would hope. There’s always going to be requirement for a business of our size and scope to have a physical medium.”
Download only would annoy me, having to wait for the download every time you want something.