I debated posting this a couple times the other day. Part of me finds hacking apart the portal.dat cheesy. Another part of me really does like to see what is in there and what might be coming our way. I decided to let the cheesy side win.
Contained within the Portal.dat file are the descriptions of some new spells that will most likely be appearing in the revised loot system. These spells range from stackable creature masteries, providing a +5 to +15 bonus, to stackable life spells, providing an additional +10% to +15% protection or +10% or +20% to our regeneration rates, to stackable item spells, providing additional damage and abilities to weapons or enhancing the protective abilities of our armor. We of course don't know how these spells will be used on the new armor, whether in conjuction with the existing spells we see or replacing them completely. Whatever the case, it certainly looks like these spells will completely change the face of the game again.
If you'd like to take a look at all the spells that will show up, there is a thread on the Vault you can take a look at.