Apparently my previous post was terrible advice, but nobody else wanted to give you better advice. (I hope somebody from a larger studio can shine more light on what they're looking for)
So please let me try to clarify by asking this: Where are you wanting to be hired exactly?
If it's at a really big studio, maybe a strict and narrow focus on gameplay will work (I'm not sure about that), but you'll also need a lot more real world experience, and sometimes shipped titles. If you don't want to get that by working with smaller studios or doing contract work, you may want to join an indie team to do mods. From what I have gathered, they usually want to know you can do a lot of work, and make deadlines; working in a well managed team is probably the next best thing to experience in another studio.
Otherwise, your best way in may be through testing.
If it's a smaller studio, or contract work (which, FYI, is the best way to flesh out your portfolio and gain experience), versatility and flexibility are going to be the name of the game. As a contractor, you may need to make entire games on your own (or, all of the programming, anyway); mobile is a common area, so you're good to have experience there. Many will have networking aspects (from leaderboards, to some form of online play- we're not talking MMO: that's uncommon).
Since I work with a small studio, and have for the past ten years worked with a variety of them, and since I've been the one (and am the one currently) doing most of the actual hiring (usually for contractors, but for employees too), I can tell you I look for somebody who is willing to tackle any programming challenges that may come up. Sometimes we'll only have two or three programmers on a project; there isn't a lot of room for specialization.
