I've been looking to migrate from Exchange-Outlook, but there really aren't any options. There just isn't an open source solution to have an integrated email / tasks / events / contacts, with consistent labels across item types and reminders.
With Outlook, i can use a custom view to see every item in a category flagged for follow-up. I can also set a reminder on a contact, or drag an email or contact onto my calendar to create an event.
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