It could be just a semantic difference, but I would prefer someone who is steadfast rather than passionate--because most work isn't poetry, it's plumbing.
Some plumbers actually like plumbing. The act of creating things, reading about new techniques/materials/tools, solving the occasional interesting plumbing problem, working with customers and other contractors (and learning about THEIR needs so they can be a better plumber). If they are that kind of plumber, they go home and read Plumberblog.com, hang out with other plumbers talking shop, etc.
It doesn't correlate 100%, but the majority of stuff I've seen by the visibly 'passionate/excited' people does indeed end up far more of a mess than other code I've had the pleasure of working on.
It can indeed just mean someone is excited about the craft, but usually, from what I've seen, people are getting excited about learning new things, and almost by definition, they don't know how to use those things efficiently. Things = libs, coding techniques, etc. Those 'things' don't have to be 'new', just 'new' to the passionate individual. In those cases, the 'excitement' is coupled with "my first time doing X".
Passionate but professional is a better indicator.
So, when a company requires a passionate programmer for agile development, you know they're deep into bullshit and buzzwords.
I'm curious because I have been burnt out at work and decided to focus on those things I mentioned. I'm much healthier and productive overall. Yet if I went to an interview I wouldn't have hours of OSS commits on projects I worked on after work to meet most job requirements.
Absolutely not. There's a full spectrum here. But if some of your hobbies/leisure time relates to your work, you're going to be more valuable to an employer (assuming that doesn't get unhealthy). It's great if it's tangential, too. It's not about logging extra hours, it's about what gives you joy. Writing code could be one thing. Reading about new tech could be another. Or reading about related skills (management, design, marketing). If you truly love it, a higher percentage of your work time will be enjoyable, too (which means more productivity and better retention).
I certainly don't blame anyone for having a diverse life. But I have two great candidates, I'll always choose the one who loves their discipline enough that the read about it and noodle with it on the side.
Now in part I'm playing devil's advocate - there are podcasts you can listen to on a commute and you can read the odd blog post in a few minutes here and there and a relatively small amount of time can make a difference - but I still think people need to be realistic about what might fit with a particular candidate at a particular point in their life and what that actually means.
I'd rather work with people I can talk to about lots of different things, not just coding and work.
But, for better or for worse, I am passionate about programming.
I prefer to be passionate about tools on hobby project, understand the real implications and usage before commit to use it in project on the job.