I think people working on Openlayers are doing more interesting works than people working on Esri API javascript.
when I am looking for basic stuff such as gallery maps, etc, Esri API is great, but if I need something more complex like a good editing tools or a different print solution where I can controll any parameter, in this case, you can become crazy.
I find Openlayers more flexible and its solutions are wider.
what dou you think?