Fred_DM: Desura is a download client like Steam, except that, apparently, you don't need the client to actually play the games. register your indies with Desura to make sure you can re-download them in the future, in the event your direct download links are taken offline.
i bought the bundle anyway. i only really wanted Hack, Slash, Loot and Defense Grid, but the remaining 3 games don't look too bad, either. went for it.
The only real similarity between Steam & Desura is that there is a client. With Steam, most games are directly linked to the client, you can't play the game without also running the client (there are some known exceptions), and the client works like a form of DRM.
With Desura you simply use the client to download your games, they are not directly linked to it, and you can run your games without the client running (though you can still use the client to start them). The client is just there for convenience, and they are also working on allowing direct downloads from the website without any need for a client (or they might have finished that).
Indie Royale & Desura are directly affiliated.