Are there any advantages to switching my @mac.com email to an @icloud.com email addess? I don't get it.
No. But Apple no longer issues mac.com or me.com addresses now that they have switched to iCloud.com. You are free to use the old address if you wish.
Apple iCloud - Pertinent Questions
Apple IDs and iCloud
iCloud- About your icloud.com, me.com and mac.com email addresses
MobileMe: About moving to iCloud
iCloud: Features that work with one account at a time on iOS 5 and OS X
iCloud: How to back up iCloud data
iCloud: Backup and restore overview
iCloud: About storage buffering
Using and troubleshooting Back to My Mac with your iCloud account on OS X Lion
iCloud: Troubleshooting Find My Friends
iCloud: Calendar Events, Reminders, To Dos, and Tasks behavior differs by application
iCloud: Distinguishing between Calendars and Reminders
iCloud: Troubleshooting iCloud Reminders and Tasks
iCloud: Manually importing data from iCal to iCloud Calendar
iCloud: Understanding where iCloud Calendars are displayed in iCal
iCloud: Reminders are called Tasks in Microsoft Outlook on Windows
iCloud: About the iCloud Web App Plugin for Internet Explorer
iCloud: Troubleshooting web browser issues with icloud.com
iCloud: Troubleshooting iCloud Bookmarks
iCloud: How spam is filtered
iCloud: Why was I spammed?
iCloud: Keeping the Junk folder consistent between webmail and OS X Mail
iCloud: How to get long email headers for iCloud accounts
iCloud: About email aliases
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