Microsoft announced IMAP support for Outlook.com on September 12, 2013.
Finally! It’s been way too long.
POP is an older protocol and only allowed the user to manage his inbox. IMAP allows the user to manage all the folders in the account, not just the inbox.
Many email services, like Yahoo! and Gmail, offer both POP3 and IMAP access. Hotmail has lagged behind and has only offered POP3 access until recently.
I like to archive all my incoming emails into folders (mostly by sender), but I couldn’t do that with POP3. I wanted to switch to Mozilla Thunderbird to manage all my email accounts (for multiple reasons; I might make a post on it sometime), but because of the lack of IMAP support for Outlook.com, I still had to keep the Web interface for Outlook.com open (and you all know how annoyed I am with it). With the introduction of IMAP for Outlook.com, I can finally dump the Web interface and switch to Thunderbird completely.