HTC One M9 should look like the M8 predecessor featuring new higher megapixel camera as well as faster Snapdragon 810. 

Samsung is expected to release a non Snapdragon 810 device and we expect to see the 20nm octa-core Exynos 7410 in the new Galaxy 6. Samsung has confirmed that it will spoil the HTC party and launch its flagship phone on the same day.

To give Samsung some credit, they did launch its Galaxy 5 phone at the same time last year  as they did it a day before the Mobile World Congress 2014. They chose the same date this time around, and so did HTC.

Samsung used the well-known phrase "What is next" as the tease the world about its new product. What chaps at Android Central show as obvious is that the invitation looks like the successor Galaxy Edge curved phone.  Where as what next to us would mean a quick trip to the bar.