Modojo have done a nice report on the The State of DS Homebrew, its a nice guide to some aspects of the DS Scene, heres an excerpt:

When I purchased a Nintendo DS my first thought was that I needed to play New Super Mario Bros. Then I knew I had to experience Kirby Canvas Curse and Brain Age, because I really wanted to explore some games that were dependent on the touch screen. I tried to play all the games I could to see all the functionality the DS offered. It's impressive to see the amount of different and creative uses many developers are putting into their DS titles, but even some of those games are being shadowed by the creativity in the growing homebrew scene for the Nintendo DS.

My initial reaction to homebrew was little more than a shrug. I summed up the entire idea very simply with: Why? Why waste time on exploring less than impressive independent titles and old emulators when there is already so much new and interesting content for the DS? Luckily, at that time I couldn't have imagined the amazing world of homebrew I was denying myself, but I can understand why I felt that way. Homebrew, as it stands, is a difficult and inclusive world to simply walk into, and many gamers could be easily swayed from doing so. Making the leap into exploring the homebrew development scene for the DS requires a little effort, and a little learning for most gamers.

Its a nice article but fails to link to this site which is the most updated Homebrew and Emulation site for Nintendo DS on the net, cant win em all eh