A communication system (30) may include a mobile wireless communications device (35a-35c) associated with an account including an ordered master set (80) of personal information manager (PIM) entries (81a-81c) for a type of PIM data. The mobile wireless communications device may be configured to store an ordered subset (85) corresponding to the ordered master set of PIM entries for the type of PIM data. The communication system may also include a synchronization server (32) configured to synchronize the mobile wireless communications device and the account by mapping an PIM entry (81d) from the ordered master set to fill the ordered subset responsive to deletion of a PIM entry (86c) from the ordered subset. For example, the PIM data can include notes, journal entries, address book contents, lists, tasks, memos, calendar content (e.g. birthdays, anniversaries, appointments and meetings), reminders, account information (e.g. email, instant message and social networking account information), alerts, RSS feeds, and social networking status, etc.