A quick reply due to my 3 yr DD crawling all over me, but one that I wanted to do......plz PM me if you want more info.....good thing I can type fast.
Shibas are great, fabulous, loving, intelligent, beautiful dogs, and I have had two for over 8 years. With that said, they are not without their problems, especially with children and other dogs!
Without getting in to it for the thirteen hours that it would take to discuss the pros and cons of Shibas, plz consider the following: as a whole, Shibas are not known to be good with kids and other dogs. I definitely have personal experience with that, and we never, never leave our dogs alone in any way with our 3 yr old. Shibas are way too primal, with the potential of "turning" very quickly, no matter what their personality seems like a second before. Neither of our dogs are good with other dogs, even after extensive training (group and private), dog park visits, etc, etc. These dogs are not Golden Retrievers.
I have never met a Shiba (we know a lot of them around here) who is good and reliable off leash. A fenced yard is preferrable, and I believe most Shiba rescue groups won't place a dog w/out a 6 ft fence. My small female can scale / jump baby gates, low fences, etc. We have a 4 ft gate when she needs to be contained (which I would never trust outside, but we use it inside occassionally), and our yard has a 6 ft wooden fence. If it was chain link, she could climb over it, I've seen her do it at a youth baseball field that we take them to to play ball in. Definitely something to think about.
A good resource, especially for a rescue dog, is Denise Roleke (sp?) at Shibas 4 Life out of Portland area.
http://www.shibas4life.us/ She is very knowledgeable about Shibas and has the best interest of the dogs are heart.
Watch / research your breeders! I believe this was said before. Temperment problmes is a HUGE thing with this breed.
Again, watch with kids. We never have our dogs out with other children in the house, not necessarily as much because of the dogs per say, but rather because I don't trust the other children around them. My Shibas don't like to be crowded in any way, and kids, especially one who aren't being taught about dogs, do that frequently.
Walking a Shiba can turn in to a big thing too. Everyone wants to stop you and comment! "Your dog looks like a little fox, what type of dog is it, can I pet him, oooh, he's so soft!" It's fun, but again, if there are kids, you have to be really careful about not having them run up to the dog. Both my dogs feel threatened when being "charged".
Another example, most kids will pet the top of the dogs head, even if they let them smell their hands. Shibas hate this, as it's a dominant move on the persons part. I try to teach kids to let the dogs smell their hands, and then pet them gently under their chin, but that's not the norm of what most people teach kids or the instinct on the part of the kid / adult. This is a big thing with my Shibas, and can make or break the experience of meeting a new person.
And, if this is an issue for you, some Shibas can "talk" a lot. Our male is very quiet and will only bark when really playing or the doorbell rings. Our female however is very, very verbal - growls while playing, barks a lot, whines constantly.
Crate training is great (really a must in my book) so that the dogs have their own "safe place".
Again, I'm typing fast, not editing, and so plz don't think this is preaching. You may have already thought of all these things!! Shibas are fabulous dogs, fabulous!, but they aren't "easy" dogs to have. If I had my preference, while our Shibas are our "first kids" and we love them very much, I would never again have a small child in a house around a Shiba. It's a far cry from my neighbor who has a Golden and can let her kids crawl all over it. That is not the norm with Shibas. A lot of people ask me about my dogs and want to get one; I would never recommend it unless their child is older.
Hope this gives you some additional things to think about! If you do decide that a Shiba is a great option for you, have fun! They are fabulous dogs, just not without things to be aware of.

Karen