People are already blogging mostly in Swift rather than Objective C, which was created in the mid 1980's.

http://www.h4labs.com/dev/ios/swift.html

Apple is doing a good job of updating ObjC but Swift already has the momentum. Apple has made it clear that they want Swift:

http://ericasadun.com/2015/04/14/swift-in-case-you-didnt-thi...

You can choose to ignore their subtle messages (e.g. use Autolayout, Size Classes) but at some point in the not too distant future, you'll likely regret not starting with Swift earlier.