I've decided to try Flock as my non-work, End of Cyberspace book-writing browser. It's intriguing. I think if I didn't already have Ecto, 1001, the Twitter widget, and other tools, I'd really like it; as it is, it might still be interesting for its ability to make it easier to watch various things going on in my networks.
Unfortunately, none of my favorite Firefox widgets work with it. That's a bit of a downside. Still, I'll continue to play around with it.