Picking Software

Myself and a friend have been creating an MMO for the last year (Both experienced programmers) along with a few others randomly helping. Where we are stuck is with what software to use. We all work for bigger companies so normally we are using their software. To give the best example of what we are going for think Dead Frontier. Its a 3D web browser MMO sort of like Grand Theft Auto 1 graphics but is also browser based. We are looking for opinions for the software we should use since we can't all agree.

Software for solving what problem?
Software to build artwork in? 3ds Max, Maya, XSI, Modo, Blender and Milkshape all have been used to make games.
Software to build code in? Visual Studio, GCC, XCode, Mono, J2SE, JavaScript and Flash have all been used to write game code in (including games that run as browser plug-ins.)
Software to serve as server platform? Apache, J2EE, ColdFusion, IIS, Nginx, Twisted, and many other server packages have been used to serve various parts of a game.
Software to solve any particular game problem? There are many, many game engines, rendering engines, physics engines, AI engines, GUI engines, sound engines, and other kinds of engines, big or small, that have been used to put games together.

However, if you've been working on this for a year, but don't even know what you're using to put it together yet... what have you been doing so far?

Over the past year we have been working on concept art, map art, stat system, player art, quest, item mall, mainly all the content which will help keep it a eventful MMO. As I said we all worked for larger game creation companies which use all their own software. None of us ever build a browser based game nor used common software. Over my career I worked mainly as a graphic designer and game manager. We are just looking for simple software and easy to use since this is just a side project.

We are just looking for simple software and easy to use since this is just a side project.

[color=#1C2837][size=2]Software for solving what problem?
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