Okay, so it sounds like the consensus is that there will be times where a digital logbook won't be a replacement for a paper/physical logbook. I'll be going home tonight and spending some time updating it then making sure I get signatures going forward.
Re: Losing the digital logbook - That's not a concern. Essentially unless I delete the files then I can't lose it since I keep everything synced between Paralog, my iPhone, Dropbox, and Jumplog.net so I've covered that.
The important aspect seems to be that currently I don't *think* Paralog for iOS/Android supports getting signatures and I'll definitely need that for ratings, according to the USPA rules. The other part is that if I go to a new DZ I'm taking a chance as to whether or not they'll be okay with a digital logbook.
Re: Looking back at old jumps and reliving the memories - I take all my notes in Paralog (check out the screenshots below for an example of all the data from my synced Neptune N3 plus example notes at the bottom). Clearly I'm a big fan of introducing more technology into some parts of the sport :)