Maybe the game could send some e-mail reminders (with a link or checkbox to opt-out, of course) for the first 2-3 days of the game, to remind the player about turns and all. I'd also add something for some time after the person has paused, like a month later (before deletion, of course), asking if they'd like to come back. If the e-mails have nice enough messages and are really only for these two occasions, it won't be too nagging.
The first thing I looked for was contacts when I started up. If, during the first week or so, an e-mail went to the individual when a message was sent to them or activity happened like looting, this could quickly give the new player a better sense of the timeing of what was going on as well as acting as a catalyst to remind them of the game. Of course this assumes they check their e-mails more often than they check the game. Perhaps twitter or facebook posts might be better for some.
Roland
