If you search for arduino in SO, you'll see there are tons of new questions in there. Should we flag them to be moved to Arduino SE?
I've been noticing that too, and we're getting an increasing number of migrations already. I'm naturally a little hesitant to move everything, since we're still in beta. Increasing the number of good questions here though may actually give us the momentum we need to graduate.
On balance, I'd say any new questions which are clearly Arduino-specific are probably worth flagging.
We just need to be careful to avoid moving stuff that's actually more appropriate on SO (or somewhere else).
I've always been overly critical in sub-sites, I think there are way too many with very similar charters and often find myself asking ubuntu questions in linux/unix because I know I'll get a better answer there (and it's not specifically ubuntu related). I often post OS-X and apple stuff anywhere but AskDifferent for the same reasons unless it's VERY apple specific. Arduino tends to questions in EE (if it's not microprocessor related, but they often shift it back to somewhere else). I've read many arguments both for and against a more unified SE set of sites, I personally would prefer to see a better tagging system between the sites, but there's meta discussion on that as well.
I think SE and SE sites do a fantastic job, but it's grown too big and needs to become more refined (that's just my personal opinion, and I know it's not shared by others, I do NOT mean to offend). I will still be sticking around here for my "go-to" answers. In fact, the SE sites are ALWAYS my first preference because I think more seasoned users DO do the research and make this a much more valuable tool.
If only lesser rated forums had the same level of quality control, well, I wouldn't be here so often lol
To more specifically answer your question, my view is "where is the question better answered?" Just because it has an Arduino doesn't mean EE is a better fit for the electronics side, but then again, SE-A is a much better fit where people haven't comprehended the datasheet (which we all know is hefty).
My personal view, think about where YOU would ask that same question.