The biggest challenge for me was learning Ruby/Rails and Postgresql. I've never used either technology before, so it was a steep learning curve. I recommend the official set up guide.
I'll be sure to check it out. I haven't used it before, either. It should end up being an interesting learning experience. Worst case scenario, I can always call it quits and fiddle around with SMF instead.
Now, I have to go back to trying to figure out a decent last name. I have a few ideas but nothing solid. I'll probably just end up waiting until phase 4 forces my hand.