I'm sure retired1af has already passed Dooble over, but I want to save anyone else some time:
Dooble is a very nice project. I look forward to really good things from it. Forward is the key word.
It's not ready yet.
At present, it's not really ready to drive, though the very browser-curious won't have any out-of-the-ordinary problems with it. I keep checking back on its progress.