Earlier today, mobile-review's Eldar Murtazin suggested on Twitter that March 14th would see a "big announcement," implying that it would cause HTC to miss sales estimates on the One that is widely expected to be announced tomorrow. Murtazin made no mention of Samsung or the next-gen Galaxy S, but SamMobile — a site well-known for its Samsung leaks — followed shortly thereafter claiming that the tweet was indeed a veiled reference to the Galaxy S IV, allegedly tied to an event in New York City.

Save the date for a big announcement - March 14 :) And keep silence ;) HTC will miss HTC One sales again :( Like it was in 2012. — Eldar Murtazin (@eldarmurtazin) February 18, 2013

The Verge has now confirmed with sources familiar with Samsung's plans that March 14th is "definitely" the day that the Korean giant plans on revealing one or more new devices, one of which is presumed to be the Galaxy S IV. As SamMobile says, we are also hearing that the event will be in the US, though it's unclear whether carrier availability will be announced at that time.

Design of the new model is said to be a "tightly-guarded secret"

As with the Galaxy S III — which was part of an effective campaign of misinformation waged by Samsung ahead of its announcement — design of the new model is said to be a "tightly-guarded secret." We're told that the company will once again emphasize features over raw specs; tricks like the eye-tracking Smart Stay were a big part of the S III's story, and we'd expect more of the same next month. "The leap in cool new features from [Galaxy S III] to the next flagship will be bigger" than the leap from the S II to the S III, sources say.

Where does that leave Samsung at Mobile World Congress next week? Expect the Galaxy Note 8.0, which has been leaked far and wide — but maybe not in final form. "That mockup [...] that has been making the rounds? That's old news," we're told. If Samsung has disguised the actual Note 8.0, it'd be following in the Galaxy S III's footsteps. When it's revealed next week, expect the real design of the midsize tablet to foreshadow that of the Galaxy S IV, which hasn't leaked at all.