After upgrading to OS X Yosemite I found that eclipse was not working because JAVA was not properly installed. I installed it and now I am able to open eclipse.
Whe
It seems to be a layout bug.
Drag one of the column headers in the device chooser where the device should be and change the column width and it magically appears!
You can also double click the device's row even when it's hidden, so you don't have to resize the column each time.