Recycling aside there are still other ways cartridges impact the environment such as packaging and shipping. But that's just my personal opinion and I know a lot of people like cartridges. I'm perfectly happy with the frame-mounted pump I have. I also like the idea of just buying a pump once rather than spending $$$ on new cartridges every time I've used them up.

I also read somewhere that regular air lasts longer in the tires than CO2. So the cartridges are really only good as a quick fix to get you home.