If you like Windows Phone, WPCentral is the place to find out all the good stuff. I.e. Apps, news, games, forums, etc. News is that Microsoft's BUILD Conference 2014 is April 2nd this year. They're supposed to unveil the release date of Windows Phone 8.1.
WMPowerUser is also very good, and generally has more rumours type of news.
I've also seen interesting news on a supposed Windows Phone 8.5 update.
Cortana is confirmed to be included in WP 8.1, their digital assistant you could talk to.