1. No one is manually releasing the refurb Minis into the store, or doing it at odd hours as a joke. They're placed into a queue and then released automatically at a pre-determined or possibly random time. Some of the odd hours releasing could have been an intentional attempt at giving more people a chance at getting one, since releasing them in the morning or mid-day guarantees a rush that only the most diligent few can take advantage of. I, for example, was able to get a 2.6GHz Quad with 8GB RAM and 1TB Fusion drive on Saturday night just after midnight PST, and that was only because I tend to stay up really late. Attempts to get one at other times had proven fruitless. So, this mixing up of the hours when new batches are released is a good thing.
2. Both the dual-drive server version and the fusion drive non-server version have both slots filled, so either is a choice for those who plan to upgrade to dual SSDs. It saves you the hassle of having to buy an iFixit kit to get the connectors for the second bay. One thing I like about the Fusion drive, is that it may be fast enough that I won't need to replace it anytime soon. I still prefer mechanical drives because of their much cheaper pricing and larger sizes, and wish the market would hurry up and make available 1TB SSDs for $75 or less. We're not there yet, so the poorer among us can make do with Fusion for now.
3. I questioned whether I should have saved money and just gotten the 2.3GHz Quad model instead, but the possibility that this could be the last quad model for a long time made me spend the money for the additional 0.3GHz of speed. I may not notice the difference now, but in a few years, having that minor speed bump will make it easier for me to take my time in deciding the next machine I'm going to buy.
4. You definitely need to make sure that you have all your ducks in a row in order to grab one of these refurbs. You should be logged into your Apple account and have a tab open to the Mac Mini refurb store page at all times. Any delay, such as waiting for the click-through via Refurb.me or Refurb-Tracker.com, could cause you to lose out. Make sure that any preferred shipping and billing addresses are already entered and accurate. And as someone else already suggested, it might be better to enable 1-click ordering with a stored credit card, even if you don't normally like doing that. Once you've grabbed your Mini, then you can disable it and delete the card.
5. I've not had any problems with Refurb.me or Refurb-Tracker.com. The emails from both have always come in at the same time. With that said, it's best to use both, just in case. There's really no reason not to.