This is pretty shortsighted. It's not the simple case of "what you can already do with two tools" that we should be thinking about. It's that stuff that you can't even imagine was possible until it integrated, in the same place, and with a good user experience.

You'll have information that's right in front of your eyes where before, the tiniest wall of separation was barrier enough to make it inaccessible or out of mind. Things will become the same, instead of just both being in the same place. This is the essence of good UX, and it has nothing to do with this specific case, but it will emerge from simple cases like this. First two things coexist, then they share, then they become one.

For a while, the iPhone was just a phone and a computer. People even said the same exact thing you just did: "why is having a phone and a palm pilot in one device any better than having them separate?" Then they started sharing features, the internet became pervasively accessible. Then everything started sharing data and features. And now we can't imagine them separate, and we have an entirely new class of thing that came out of it that basically enabled a revolution.

Eventually programming could be the same. Programmers probably have the highest tolerance I know of for compartmentalization of tasks and poor interaction design and data visualization: they are extremely intelligent and have the ability to tie things together in their heads and break down tasks and tools ad hoc. But when you don't have to do that, when programming becomes easier and more fluid, things will start happening that simply couldn't before.

We can only dream of the kinds of advancements in our tools that are yet to come.

i see people saying less context switches. but isn't this the exact opposite? it's way more context switches?

isn't this the same as having our mails popup up notifications every so often or your gmail aggregating twitter and Facebook, because people thought it would make them more productive

You're creating a strawman. I can't see why Github would make the mistake you believe they'd make as they don't have the self-interest that Facebook and Twitter have in killing your focus with an onslaught of notifications.

I think you could expect all forms of notification to be hidden by default.

It would actually likely improve your ability to concentrate. You would be able to switch into another mode of a developers workflow without needing to context-switch onto an often focus-distracting browser.

Anyway, my core point was that there are a combination of features that allow the creation of a new holistic programming experience. I am not arguing its correctness and I am not arguing that it would suit everybody. :)

Exactly - making context switches cheaper isn't very helpful if you're doing so at the expense of making context switches more frequent[0].

[0] and easier to do "by accident"

This is a silly argument. You're all assuming this type of integration will be have the UI quality of your dishwasher.

Of course context switches and irrelevant information will be distracting if done poorly. This is a UX challenge—not a reason to abandon the idea.

Having the focus you need during concentrated tasks such as coding, while also enabling the integration of other tasks—such as high-level team context awareness and collaboration—is the key design challenge. Done well, it would be a killer app.

Done poorly, as with anything, it will fail miserably.

Programmers have a poor reputation for UI design prowess, and programmers tools are sadly usually made by programmers, and thus carry the same reputation. Very few amalgam programmer/designers exist to bridge the gap of motivation and ability to design a better toolset. But they do exist.

Let's be optimistic, shall we?

They're not quite the same. Those are push-notifications. Push/pull is orthogonal to what application you use for which purposes, especially if you have a desktop were you get such push notifications thrown at your peripheral vision no matter what application you're in.

Potentially fewer context switches and interruptions? I know for me the browser is a potential landmine of distraction, it might be handy to be able to limit that.

I think somewhere along the way we lost sight what context switching really is. Just because you put a different activity in the same tool doesn't mean there's not a context switch when you move to that activity.

Do you really think there's not a context switch when you change from writing and thinking about your own code to reviewing pull requests and comments?

There may be benefits to integrating extra functionality, but let's not imagine there's no cost to changing your mode of operation just because it's in the same tool.

Minimising context switching is a big part of improving programmer productivity, as I'm sure you're aware. This may not seem like much, but large increases in productivity can be achieved through small increases building up; every little helps.

Plus, it's cool.

I think you confused context switching with app switching. Yes having Github activity in the text editor means less app switching, but you are still context switching; from writing code to reading comment, which is the real productivity killer. Why not just add gmail to that text editor while we're at it and save ourselves some time?

Same reason there exist plugins to integrate Git status & diff in Sublime: it's useful for some of us.