With the next generation of among consoles, the manufacturers want to take full advantage of Internet connectivity. Since most households, especially those with gamers, have broadband Internet service, Sony and the other console makers have decided to assume that pretty much all users will connect their consoles to the Internet. This could lead to some very cool and interesting features but on the other hand it could lead to some problems and restrictions.
On the positive side always on Internet connectivity could let you play games on the go with a PlayStation Vita, or use your saved games and characters on your friends PS4 using your password. Game developers could make some cool features too. I'm sure once the PlayStation 4 is released we will see some pretty neat features.
But there are downsides to requiring an Internet connection. Of course there's the obvious fact that some people won't be able to play games at all. And what about those who might only have Internet acces some of the time, such as RV or boat travelers. And what about people who live in rural areas who don't have reliable Internet service? And everybody has service interruptions no matter how good their service is. It would suck if you couldn't play games if your cable service was out. Imagine if the cable was out so you couldn't watch tv or go online and now you can't even play video games when the cable is out. This has a major drawback in itself. But perhaps the biggest drawback is that games will be registered to one specific PlayStation and you can't just pop out the disc and bring it over to your friends house to play in his PlayStation. And this would completely eliminate the secondhand video game market. No longer can you buy, sell, or even trade your games. But Sony has announced that they will allow users to temporarily lend games to their friends. Its not as simple a just taking the game disc to a friends house, you have to go into the game settings and select the option to temporarily disassociate the game with your PlayStation. It's good that Sony will let people lend games to each other, but it isn't good that you even need to do anything before the game can be used on another console. Of course all this could change in the months leading up to the launch of the PlayStation 4, so we will see how it turn out once we get our hands on a PS4 ourselves. Until then we can only go on what Sony says.