Since the guys from 37Signals were the ones to develop RoR, I wouldn't be surprised if the version they use is slightly (if not quite) different from the "public" version, so I don't think they're a good comparison.
I've tried Wavelog, but I'm not hugely impressed at the moment. For one it seems you can only have one blog on there, as well as the fact that you can't edit old posts, nor delete them.
Does this mean that they're going to take jaiku out of action for a while like they have done with grand central? For that reason alone i'm glad they haven't bought twitter.
I did a review on Zend studio 3 about 3 years ago and loved it. The only issue I had was that back then it had a habit of running a bit slowly sometimes (I think it's written in Java). However, I haven't used properly since but aside from that it was a really good piece of software.