And so it happened to you too... It was quite for-see-able, as i perfectly understand why you are leaving - i left for the same reason. Old go... new come. As the children grow, so do the adults, and, after a while, they become the deceased ancestors that founded the empire in which their children spend their time. Everypony was a village, now a town. Who knows what the future of this forum is with the present admins, but if it countinues like this it'll be a very bright future.
In one of your first posts you said "Slow down, even Rome wasn't built in a day.". I find that quite fitting for this situation - Everypony is growing like Rome. Only 10 months and already we've established a well-functioning forum with lots of posts per day. We're even more active than some forums with thousands and thousands of members, forums that have been standing on their own for years. You, Twif and me come from such a forum, Grey. Derpy as well, Grey. We all sat down and founded this place. Quite officially Derpy wasn't part of the founding team, but he still was here from the very beginning and look at him now - the lead admin.
10 months may seem like a short time. It might be. March 21st... spring was knocking on the door. It's winter now... It'll be a year in just 2 months. A full year of an community that has been striving towards popularity for quite some time. The first users that helped grow this forum are all gone, if not all, then most. Pac, Bamboo, Sedaheht and other great, fantastic people that appeared at the right place at the right time, wonderful people that took us three by our hands and helped us reach the platform on which we are now. There are way more platforms to come, though; whether you see this as an end of a chapter in your life or as a new beginning is of no matter - Where we stopped, others'll carry on, Grey.
I am not really great with speeches on English, so i can't really express how this is feeling. But i consider it like this: we're looking into a mirror and holding an old photo of ourselves. We see the difference of then and now. We might not be as handsome as before since we're older, but our souls are.