But think about that more -- what else could be associated with drinking coffee? People who drink coffee every day might be more likely to have a job, which means (in the US) that they're more likely to have health insurance and higher socioeconomic status, which can cause increases in life expectancy too.
Which suggests that it could be the case that if you're thinking about drinking coffee every day, you've probably already benefited from the positive effects regardless of whether you actually go ahead and drink it.
While I don't think we're going to be able to isolate the measurement of positive effects, we can say one thing: while we can't measure causal positive effects on health, we're at least not seeing strong negative effects on health from moderate coffee drinking.
The argument's just over whether coffee is causing the slightly-better health that people who drink it experience, or merely correlating with it.
If you're asking for opinions: after having been a regular (sometimes extreme) coffee drinker for more than 20 years (until about 3 months ago), I'd say no. Whatever disputed positive effects it might have (mildly stimulating, supposedly preventing depression, for me personally it seemed to prevent distraction mostly, but so does suitable music... ), we know for sure that it screws up your sleep and, in many cases, digestive system. I sleep better and am more productive now (I think) than before and on top of that I also got rid of an annoying routine (making coffee N times/day) and a resource I depended on (and might miss during zombie apocalypse, for example). But for people who smoke for example, it's probably negligible either way.
Otherwise you may fuzz up your concentration along with your gastrointestinal system.
For instance:
For people who drink 1-2 pots a day, I've seen it cause gastrointestinal issues, ulcers, reflux, and other issues.
Seems to cover a lot of studies, but it could be a "submarine" post. http://www.paulgraham.com/submarine.html
You be the judge. The safest way to do it, is not to overdo it.
Thus I suspect coffee is "healthy" for some people in much the way that an albuterol inhaler is good for some people: If you have some mild health issue which is treatable with stimulants, having moderate treatment as part of your diet is better than having no treatment. If coffee is something you seem to need, you might do well to look into things like allergies, respiratory problems, etc.