I don't really think player-owned stuff would work very well, and in my mind it comes a looong way down the priority list, way after fixing the bugs in the background sim, the bugs in PowerPlay, etc. Make the core game work well, then think about something significant like player-owned stuff.
I'm very much in favor of guilds. Every significant, long-term MMO experience I have had has a guild at its center. Social interaction increases stickiness (go read the Blizzard annual reports to their shareholders if you want more detail). I'm very confused at the people who don't want guild features. Right now I have a friends list that I can only ping individually, I have no guild or faction chat, I have no way to identify that a Commander is part of a particular group, and I must use out-of-game tools for all my organization. It feels really clunky.
Given the P2P limitations (32 players, more like 10 frankly), Private Group and Solo modes, I think it's extremely unlikely that large griefer groups would form, as some in this thread seem to fear. As with almost all things in life, guilds can have a positive and negative effect, and I believe the positive would outweigh the negatives.
At the very least, it would be nice to have a statement from FD about their intentions, once they've had a chance to think more about the issue. I'm glad they took the time to post a poll, but polling is a very inexact science, especially on the internet.