For reasons I've never been able to understand, skeletons imported from the .dae format in Maya end up displaying with incredibly tiny joints. This includes those that where exported from Maya to .dae, and then imported back in. I have yet to figure out how to fix this. The small joints makes selection difficult, as they're often as small as single pixel until zoomed in very, very, very close. They completely ignore Maya's own settings for joint display size.
It was the opposite for me, they were extremely large, and just looked like a great big blob. It may have only been because I had just freshly installed Maya 2012 on a new computer though, and thus hadn't yet adjusted the display settings yet.