Top tech headlines: Yahoo! CEO fired, Arrington leaving TechCrunch, Google buys Zagat

Hot topics in the tech blogs for the week ending September 9 include Yahoo!’s CEO fired, Michael Arrington and AOL at odds with one another, Google purchases Zagat, HTC sues Apple and Twitter reaches 100 million active users.

Yahoo! CEO Carol Bartz fired
Yahoo! CEO Carol Bartz was removed from her role as Chief Executive Officer of Yahoo! by the Board. Upset that she was "fired over the phone by Yahoo Chairman of the Board," Bartz later told Fortune that "[t]hese people f--ed me over."

Michael Arrington rumored to be fired by AOL
TechCrunch founder Michael Arrington is at odds with his employer AOL (who recently purchased the noted tech blog) over the concept of "editorial independence." Fortune reports that "AOL executives have decided to terminate Arrington," but the how and when has not been finalized.

Google buys reviews site Zagat to enhance local services
Google acquired respected review, ratings and recommendation company Zagat and announced that they intent to collaborate with Zagat to "bring the power of Google search and Google Maps to their products and users, and to bring their innovation, trusted reputation and wealth of experience to our users." Search Engine Land said "[t]his is huge news for Google (capital 'H') and for local."

HTC Sues Apple , Apple wins sales ban on Samsung tablet 
Android phone maker HTC Corp. is reportedly using patents it purchased from Google to "pursue new infringement claims against Apple." The patents were originally owned by Motorola and will be used by HTC in court to prove that Apple’s "Mac computer, iPhone, iPad, iPad, iCloud and iTunes are infringing patents for a way to upgrade software wirelessly," among other things, reported Bloomberg. Meanwhile, Apple has won the latest war against Samsung in Germany where the court ruled that Samsung had copied the design of the iPad. The latest ruling upholds the temporary sales ban on Samsung's tablets within the country. 

Twitter reaches 100 million active user milestone
Twitter announced that 100 million people are now logging on to the social networking site every month to share their opinions with their followers and to find out what's happening in the Twittersphere. Fifty percent of those users log on to the site every day said Twitter but around 40 million of the 100 million active Tweeps don’t tweet. Around 5 billion tweets are sent every five days added Twitter.