We are currently building a new subscription center and wanted to throw out a question to the community. What have you seen as being successful and not successful when creating an email preference center?
I'd start by checking out Josh Hill's blog. He's does a great job in covering ideas to lay out a full subscription center. Josh Hill
Building a Full Subscription Center in Marketo - Marketing Rockstar Guides
I'd also do a search here for tons of threads.
As for "what works" it's really about your audience. What would work for them? What would help you communicate more precisely?
For starters, I'd make sure that you actually plan on sending enough different types of emails to justify an email preference center. While they're great in theory, they won't make sense for every business. Also, be sure to be clear about what types of emails you're sending for each list someone gets themselves on, as well as the frequency of sends for that list.
Another thing that we found helpful at a previous role was to include the list that someone was on for a mailing that they received. So, the unsub link would contain something like "You have received this email because you're opted in to receive event communications from eMarketer. To unsubscribe or manage your preferences, click here" This way it was easier for people to know what type of communications to opt out of.