Cool? Yes. But is there anything besides "cool"? Probably not. Seriously, what's the reason to build web ide? The reason for some sort of web word process, i.e. google docs, is clear. But IDE? Thinking about pros of this tool i can only pick three, first one is access from anywhere, which is not that important since most developers can take their laptops and all the tools they need, when they need to. Second one is editing source files simultaneously which is rarely required for programming work. And the third one is an ability to deploy to different servers and architectures, testing you app on lots of different hardware and OSes, which is pretty cool, but it's hardly an ide job. But having only this three cons (name others?) is not a very valuable argument..
Now, even i don't see the point in this things, to get something useful out of it, it should provide two features, first one is extensions language which would be capable of expanding the functionality of ide, only not plugin-like shit, but more as elisp for emacs. And second one is an ability to edit files on some user provided machine, think or slime & swank.
1. My development machine, being a notebook, is always too slow. Being in the "cloud" this could be fast enough for building and deploying.
2. My internet connection at home is too slow for fast turnaround (1 mbit/s). With this I would not have have to upload the built packages to the deployment machine. Assuming the IDE runs on the deployment machine.
As a Java developer (most of the time) I would need this to be a Java IDE though. :-) But there is no reason that this would be impossible.
I think the main advantage is that there is no need to set up a dev environment (at my place of employment this can take several hours). What follows is that testing and bug fixes can be made much easier, especially for newcomers to an open source project.
Well, for one, poor students wouldn't have to drop cash on a desktop IDE or a faster computer to develop it. Since my previous laptop broke, I've been working on a netbook for months (and got quite used to it), but have had to resort to campus computer labs if I have to do some Visual Studio, Delphi, or SQL Server work.
When my teachers learn that everything I turn in I do it in class, and not from home, they are genuinely surprised that I am able to do things well and on-time. With this, I can do some work on my netbook, download it at the labs, and keep working from there.
