The Netbeans platform is actually really easy to work with. I prefer Netbeans to Eclipse so I'm probably biased, so I'll take a look at Eclipse's framework before I decide. Netbeans has many great features though, so I'm probably going to go with that.
A custom map editor was something I'm certainly planning on doing. I'm hoping I can do something with Tiled maps.
A custom profiling thing seems really hard to code so, unless I can find some help with that, I don't think that's going to be in it soon. Probably the same for a visual debugging tool because I don't even know what that is.
I'm going to start with an integrated resource loader and maybe an entity framework based off the component-based entity tutorial from the wiki. One of the reasons I want to use Netbeans is because it has a Wizard creator which could be handy for automating the creation of entities.
I'm going to make this Open Source, though, and I'm hoping everyone will contribute code snippets and the like so we can get more people to use Slick (and my app

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