I could go on and on on why this is the best possible finale for the series they could have ever written, but I won't... It would be too long and philosophical. All the answers you may have are answered, but not in a cheesy 90s way, but in the most humane and sincere way: with hope. I cannot address it more: go see this episode for yourself.
The one thing I can only say is that 8 seasons, 160+ episodes were worth it JUST to see this episode and understand all of its magnitude. After this episode you will never be able to listen to Peter Gabriel without crying again, maybe you won't even feel feelings so strong as the ones at the end of this episode. i am not kidding: I'd take this series over many aspects of real life!
Best TV series I have ever seen and that I'll ever get the pleasure to see: pure and inhumane perfection.