[Timeframe]
The general consensus is that this is 7 years after the Rogue attacks.
[NPCs]
There have been a lot of minor edits to NPC names, and I'd like to point them out to you so you don't get too confused. There are plenty more NPC's, but these are the ones you should know about for now.
The IPC are now known as the NetPolice.
NewServ is now News Server.
??? has become Anonymous.
The big company that does a lot of Navi work is now NanoPengi.
Soryu and Persephone are now the Chip shop owner and trader, respectively.
Suitachi and Tempoman are now the Navi Shop and NCP trader, respectively.
Don is now a reporter.
All canon characters (Netto, Meijin, Higsby, etc) are gone, so please don't reference them.