So I need to pay $5 a month to stream my own local content to my PS4? Eff that.
I found it kind of funny how people blew up at this announcement. You should've seen the comment thread on IGN!
No, the monthly fee that you're talking about (the Plex Pass subscription) is
not specifically for streaming content to the PS4. Plex is a free program (for PCs), so rather than just ask for money (to support the company) and give nothing, they setup Plex Pass. Plex Pass mostly provides access to beta features, which is what the PS4 and Xbox One streaming are. Although, Plex seems to be pushing to add more features to Plex Pass to make it have a bit more value, but the features aren't really needed for core functionality.
So, in short, no, the fee is to use Plex. The problem is that Sony has taken too long, and Plex is currently the only way to stream media. However, I would bet dollars to donuts that the Plex setup will probably be better than Sony's setup. I've tried it on the X1, and it works great. It's pretty much just as good as the Windows 8 Metro app, but with a lot more categorization and suggestions.