VOIP. WOW ok here comes the can of goodness.
The asterisk system is capable of accepting and dispatching phone calls in many many different ways.
When you say "VOIP" (Voice over Internet Protocol) you are talking about a specific carrier set that does not require any additional hardware on the asterisk system. Voip providers will hand off either as a SIP service or an IAX2 service. IAX2 is a little better for bulk call drop off, like say, between two offices with 20+ concurrent calls on each station. In your case, it doesn't matter. Just accept it. I have my service through VIATALK
http://www.viatalk.com/ who run something like 100 year for one phone number and "unlimited" phone calling. (Your actually limited to something like 4000 a month or something. Fine print is fun) They work wonderfully with asterisk systems.
The other option is that you can get FXO cards (Read here about FXO vs FXO
http://www.3cx.com/PBX/FXS-FXO.html) , preferably from digium as they are the best supported on the asterisk system
http://www.digium.com/en/. This means you use your standard every day phone from Ma Bell and the system routes it however you program it too.
You can then dispatch your calls in many creative ways. You can use FXS cards to deliver your phone calls to standard phones. When you think about an FXS line, imagine it like a phone line coming in from your phone provider. You can run many phones off it, but you can only place one call at a time. If you got 3 standard phones and plugged them into 1 FXS port, you could listen on each phone to the same conversation, but only have one phone call per FXS port. If you had 3 FXS ports and each phone plugged into eachother, they all are treated like their own phone line. You could call your kitchen phone from your office phone and your kitchen phone would ring like an outside caller was ringing in.
Another option is to have IP phones. IP phones can either be soft or hard. I belive the phone system will turn your Media Directors into soft phones. Soft phones are phones that are not stand alone dedicated phones. They are software running on multipurpose hard ware. So all your computers can be registered as soft phones. Hard phones are IP phones, like this phone
http://www.amazon.com/Soundpoint-IP-331-SIP-New/dp/B002Y37QOY/ref=sr_1_2?ie=UTF8&s=electronics&qid=1265149510&sr=1-2.
This phone would plug into your network like any computer, and speak to the server through this means and would not require additional cards.
As far as routing your calls are concerned, the sky is literally the limit. The asterisk system is capable of handling voice mail, transfering calls from phone to phone, and would meld all your incoming lines. For instance, you have 2 personal phone lines and 1 business line. If a phone call enters your business line the system can bring on an automated attendant stating that they have reached whatever business you run and to hold just a moment while they find someone to help them. Then it can ring your office phone, then the rest of the phones in your house if you choose, or if you have outgoing lines available, your cell phone. The same can happen with your personal lines. You get to choose what phone lines are associated with what phones, and how they ring. The setup can get complex, at least for me but that is because I choose to edit the conf files by hand, but the possibilities are truly endless. I do not know what LinuxMCE does as far as ease of setup.
Sorry for the long response. I am used to glazed looks and rushes for Tylenol after my explanations of this topic. Please let me know if you need something clarified.