Choosing systems to manage your content is mostly a matter of figuring out what sort of content you currently have, how you use it, and where you want to have access to it. Systems to manage and distribute content can involve all kinds of technology - media servers, network attached storage devices, cloud storage systems, audio or video streaming systems, PVRs and Video on Demand, just to name a few.
The right components for your needs
If you're the kind of person who has a zillion MP3s, CDs, DVDs and Blu-ray Discs stored up from years of meticulously crafting a humungous media collection, you may want a powerful and flexible system to keep everything in order and give you easy access. It's also likely that you'll want access to your own content, from anywhere.
In this scenario, some type of media server with a large network attached storage device is probably a good idea. Not only will it give you access to all of your content from anywhere, but it'll also help you keep everything organised. Some more serious media servers even give you the option to pre-load thousands of movies into your system before it's installed.
On the other hand, if you're rarely home and only require a bit of background music or the occasional new movie when you are, it may even make more sense to just have fresh movies available using a video on demand system, and a system that incorporates an iPhone dock or digital radio. A PVR that's programmed to record your favourite TV shows will mean you can watch them at your own convenience too, and may let you play them back over the internet while you're travelling.
Keeping it simple
Because there are so many different ways to record, store, manage and enjoy content, it's very easy to end up with a system that's fiddly and over-complicated. If you're technically minded, it's possible to set up an entire content management system yourself using a variety if different components and parts. Having said that, if you want a system that just 'works' and does exactly what you need it to, having a complete content management scheme designed and installed for you as a part of a larger AV setup will ensure that all of your hardware is compatible, and that it works exactly as you want it to.