I mostly commute, and I mostly wear fingerless gloves.
For short rides in nice wx, no gloves are ok.
For almost any rides in cold wx (Minnesota winters), full gloves are mandatory for me.
Fingerless I wear a lot for two reasons. First, the padding does help if I'm biking more than a few miles. As cdotbois points out, hard pavement and thin padding on the handlebars and you'll start to feel it pretty quick. Second, I use a grip shifter, and full gloves are kind of awkward to shift with (over- or under-clicking), so fingerless is the best compromise.