Samsung vs. Everybody Else
On the Galaxy S4 Announcement (by Koushik Dutta)
More important than what Samsung talked about is what they did not mention, not even once: Android or Google.
With every new release of their flagship phone, Samsung cannibalizes and reimplements more and more Google services-- media storefront, voice command, translations, cloud storage, music, instant messaging, photo sync, video chat, etc.
The lynch pin in the Google ecosystem is Google Maps and Google Play.  This is the carrot and stick that prevents Samsung from forking Android altogether: want these Google Apps? Then play nice in the Android playground. You can't fragment Android, and your search provider must be Google Search.
A lot has changed in the past 2 years. Now commanding 40%+ of Androids sold, Samsung could certainly release their own app store, and actually have it be taken seriously. I wouldn't like it, but if Samsung decided to ship without Play on all their 100M+ devices they sell a year, I would be forced to comply. A strategic partnership with Microsoft/Bing could get Samsung their own Mapping solution, and this would nix their dependance on Google.
It's interesting watching Google and Samsung game theory out all possible outcomes-- patent IP was not the only reason Google purchased Motorola last year. That acquisition was a hedge on Samsung deciding to go nuclear. And Samsung replicating and commoditizing Google services the defensive (and offensive) response.
The launch codes have been entered, one of these players is going to push the button eventually.
 You can still get Gmail with IMAP/ActiveSync, etc. I don't consider this a selling point for Google. Ie, the Mail client for Windows 8 was actually Pretty Damn Good with Gmail. I'd also be willing to bet that Microsoft would rev share Bing if it shipped as the default on Samsung phones.