Scheduling and managing events using Outlook.com calendar
I definitely would NOT use the Outlook Calendar, but it's the only option since I use a Windows Phone. Actually, to be honest, it's not the only solution, the other solution would be for me to actually remember all the birthdays :-)
All I need the birthday notification for is to call those respective people on their birthdays and get them some sort of gift.
Given that the phone I have with me all the time everywhere, having it notify me would have been the most convenient solution, but I guess MS does not want that, as they don't care how good their products are.
No wonder the WP has a abysmal market share, as it's well deserved in some ways (though totally not deserved in many other ways, to be honest).