I use
DistroWatch,
OSnews,
AtomicFire,
Linux Weekly News,
Slashdot and
Google News.
A few notes.
Distrowatch has new distro releases daily and a newsletter that highlights the releases of the past week plus has Distros that are waiting to get onto the distrowatch list, a featured distro with an in-depth review, and other things. It comes out on Mondays.
OSnews has news on all operating systems. and is updated daily.
Atomic Fire is a new, tech news site, but I haven't seen much on Linux or Open-Source software on it. It is updated once every 2-3 days
Linux Weekly News covers a number of Open-Source topics. The downside is that the news is a week old unless you pay (I think) $5 a month. I believe they release a new edition on Wensdays.
Slashdot covers a wide variety of geeky and nerdy news including but not limited to: Linux, Open Source, Science, Books, and computer companies. This updated at various times during the day so it's worth visiting 2-3 times a day.
Google news is a collection of news articles from various sources and their sci/tech section has quite a bit of news on Linux and Open-Source. It is also updated several times a day.